MAI COMPANY CONFIDENTIAL FIELD INFORMATION BULLETIN SERVICE GROUP(S): MICRO,MINI,LARGE MFG: BASIC FOUR NACS TYPE(S): N100 MFG. MODEL(S): Environmental CATEGORY: HANDBOOKS DESC: Handbook *** TABLE OF CONTENTS AS OF 11/19/94 *** FIB 00001.General Information.........................................07/14/89 FIB 00002.Power Distribution Diagram, 4-Wire Wye Grounded Input.......07/14/89 FIB 00003.Common Transformer Configurations...........................07/14/89 FIB 00004.Basic AC Wiring Description.................................07/14/89 FIB 00005.AC Wiring Notes.............................................07/14/89 FIB 00006.Isolated Ground Receptacles and Circuits....................07/14/89 FIB 00007.Wire Color Codes and Characteristics........................07/14/89 FIB 00008.Computer Room Circuit Breaker Panel.........................07/14/89 FIB 00009.Hazardous Use of an Isolated Ground Rod.....................07/14/89 FIB 00010.Isolation Transformer Referencing...........................07/14/89 FIB 00011.ECOS 7100 and 7106 AC Line Checkers.........................07/14/89 FIB 00012.Building Wiring Verification................................07/14/89 FIB 00013.Tracing AC Wiring...........................................07/14/89 FIB 00014.AC Line Treatment Device Performance Summary................11/14/94 FIB 00015.Dranetz 606-3 AC Line Analyzer Notes........................07/14/89 FIB 00016.BMI 2400 & 4800 Environmental Monitor Notes.................07/14/89 FIB 00017.Techniques for Protecting RS232 Devices from Transients.....07/24/89 HANDBOOKS-BASIC FOUR-Environmental------------------Table Of Contents Pg01 of 01 FIB 00001 07/14/89 *** General Information *** I. This handbook replaces the original Sorbus Environmental Handbook of Computer Room Problems. There are some figures in the original Handbook which cannot be put into the system since we are limited to the use of the terminals standard ASCII set of displayable characters. As always, if you see anything you feel should be added/modified in this handbook, please contact Norm Jones. II. Special tools referencd in this handbook: ECOS 7100 Ground Chek ECOS 7106 Accutest ECOS test adapter kit TP2 ECOS L5-15 & L5-20 twist lock adapters Amprobe RS3 AC ammeter ACL model 300B static meter III. This Handbook is the hardcopy material for the Computer Related Environmental Problems videotape. ORIGINATOR: N. Jones HANDBOOKS-BASIC FOUR-Environmental------------------FIB001 Pg001 FIB 00002 07/14/89 *** Power Distribution Diagram, 4-Wire Wye Grounded Input *** Circuit Breaker Panel _______ | | +----------|--o\o--|--Phase A | +--------|--o\o--|--Phase B | | +------|--o\o--|--Phase C | | | +----|-------|--Neutral | | | | +--+ +--Ground | | | | | |_______| ___ | | | | | _____ | | | | | | | | | | | Service | | | | | Circuit | T | | | Entry | | | | | Breaker | R | | |_____ _______ | | | | | Panel | A | | | | | | | | | | | _______ | N | | | M | | | | | | | | | | | S |---|---|- E -|--|--o\o--|--Phase A---------+-|-|-|-|--|--o\o--|--Phase A | F |---|---|- T -|--|--o\o--|--Phase B---------|-+-|-|-|--|--o\o--|--Phase B | O |---|---|- E -|--|--o\o--|--Phase C---------|-|-+-|-|--|--o\o--|--Phase C | R ++--|---|- R -|--|---+---|--Neutral---------|-|-|-+-|--|-------|--Neutral | M || | |_____| | +---+--Conduit Ground--|-|-|-|-+--+ +--Ground | E || | | | | | | | | | | |_______| | R || | B | |___|___| | | | | | |_____|| | U | +----Isolated Ground-+ | | | | | Computer Room | | I | | | | | | | | Circuit | | L | B | G | | | | | | Breaker | | D | U | R | | | | | | Panel | | I | I | O | | | | | | _______ G | | N | L | U | | | | | | | | N | | G | D | N | +-|-|-|-|--|--o\o--|--Phase A D | | | I | D | +-|-|-|--|--o\o--|--Phase B | | W | N | | +-|-|--|--o\o--|--Phase C R | | A | G | R | +-|--|-------|--Neutral O | | L | | E | +--+ +--Ground D | | L | | F +------------|-------|--Isolated | |___| | |_______| Ground _______|___________________|____________(Earth) / / / / / / / / / / / / NOTES: 1. Voltages: phase to phase - 208 phase to neutral - 120V phase to ground - 120V 2. Services that may be utilized from each panel: a. three phase 208V b. single phase 208V c. single phase 120V HANDBOOKS-BASIC FOUR-Environmental------------------FIB002 Pg001 3. The isolated ground wire should be run in the conduit with the phase wires back to the service entry panel. It must not be connected to the panel but must be on an isolated ground bus. The isolated ground must be used to provide ground for CPU, Disk, and Tape circuits; and each of these circuits must have isolated ground receptacles. 4. If the computer room is in a high rise building and not on the ground floor, the best ground available may be a vertical steel beam which is contiguous into the earth. This can normally be found near the elevator shaft. ORIGINATOR: N. Jones HANDBOOKS-BASIC FOUR-Environmental------------------FIB002 Pg002 FIB 00003 07/14/89 *** Common Transformer Configurations *** 1. 120/240V Single Phase System *----------Hot * * Hot to Neutral or Ground = 120V *-------------------+ Neutral Hot to Hot = 240V * | * --- Ground *----------Hot - 2. 120/208V Grounded Wye Three-Phase System *-----------------Phase A * A * *-------------+---Neutral A to B = 208V * * | B to C = 208V C * * B ----- Ground C to A = 208V * * --- * * - A to Neutral or Ground = 120V | | B to Neutral or Ground = 120V | +----------Phase B C to Neutral or Ground = 120V | +-------------------------Phase C 3. Center Tapped Delta Three-Phase System A *---------------Phase A * * * * A to B = 240V * * B to C = 240V C * * B C to A = 240V * * * * * * * * * * *-----Phase B | | A to Neutral or Ground = 208V | +----------------Neutral B to Neutral or Ground = 120V | | C to Neutral or Ground = 120V | ----- Ground | --- | - | +---------------------------Phase C HANDBOOKS-BASIC FOUR-Environmental------------------FIB003 Pg001 4. Corner Grounded Delta Three Phase System A *---------------Phase A * * A to B = 240V * * B to C = 240V * * C to A = 240V C * * B * * * * * * * * * * *-----Phase B A to Ground = 240V | B to Ground = 240V +---------+---------------Phase C C to Ground = 0V | | ----- Ground --- - ORIGINATOR: N. Jones HANDBOOKS-BASIC FOUR-Environmental------------------FIB003 Pg002 FIB 00004 07/14/89 *** Basic AC Wiring Description *** CIRCUIT BREAKER LOAD PANEL DEVICE _________ _______ | | | | *------HOT-----------o\o---------black-----------------\ | * | | | / | * | | | \ | * | | | / | * | | | \ | *---+--NEUTRAL-------------------white-----------------/ | | | | | | ----+--GROUND--------------+-----green-------------+ | | | | | | ----- |_________| |_______| --- - This figure shows a single phase transformer feeding a circuit breaker panel with one circuit breaker and one load device. The HOT wire is the only wire which passes through a circuit breaker. The neutral wire or grounded conductor is passed through the circuit breaker panel and the same is true of the ground wire or safety ground. No disconnects are allowed on either neutral or ground wires. Note that the neutral wire is connected to the ground wire and both are connected to earth ground. Because of this electricians frequently fail to realize the significant differences between neutral, safety ground, and earth ground. Each element has a different purpose even though they all are connected at one place. It is important to note that neutral and ground should be connected at only one place in a building. If the transformer is outside the building this tie point will be in the electrical service entrance area. Normally this is accomplished in the first panel inside the building, in metal raceways between panels or in the meter base. If the transformer is inside the building it should be connected on the secondary side at the transformer. In either case neutral and ground must be connected at only one place in the building. The reason for neutral's connection to safety ground and to earth ground is to limit the voltage in the circuit relative to earth and to provide a return path for fault current in the event of a hot to ground short. Without this connection the voltages in the AC circuit could drift to any level increasing shock hazard. Note that neutral is not ground, it is a current carrying conductor as is the hot wire. Also if it is carrying any current at all it is not at ground potential at any other point than at the one tie point in the service entrance area. HANDBOOKS-BASIC FOUR-Environmental------------------FIB004 Pg001 The ground or safety ground wire is tied to earth ground, to neutral, to the circuit breaker panel (and all other metal enclosures), and to the chassis of the load device. The purpose of the ground is two-fold, to hold the metal enclosures at a touch voltage that is safe relative to earth and to provide an alternate path for fault current back to neutral to cause an overcurrent device to trip in the event of a hot to ground short. By code the ground or safety ground can be either a wire or metal conduit. For our computers and critical I/O devices such as tape and disk drives, a green wire ground is required, conduit ground is not acceptable. The earth ground is a connection into the earth which may be driven ground rods, water pipes, building steel, or a combination of these. The purpose of the earth ground is to provide the earth reference for neutral and safety ground. It also serves to provide a path back to earth for high energy impulses relative to earth such as static, lightning, and RF. ORIGINATOR: N. Jones HANDBOOKS-BASIC FOUR-Environmental------------------FIB004 Pg002 FIB 00005 07/14/89 *** AC Wiring Notes *** All receptacles used by the system (CPU, disk, VDT, printer,etc.) must be three wire type, correctly wired with a ground path to neutral of less than 2 ohms impedence. Ungrounded circuits cannot be used. All dedicated isolated lines must have: 1. Isolated ground receptacles (I.G.) 2. Three wires dedicated to that circuit (dedicated hot, dedicated neutral, and dedicated ground). 3. Dedicated metal conduits (there should be only three wires inside a conduit feeding a dedicated isolated ground circuit). 4. Insulated ground wires (bare wires are not allowed). 5. Ground wires that connect directly to the service entrance ground (at the neutral/ground bond for the building) or to a vertical steel beam which is contiguous to earth and part of the building ground (best ground available in older high rise buildings). The conductor that connects neutral to building ground and building ground to earth ground (ground electrode) should be no smaller than the supplying neutral. The only place neutral should be connected to ground is at the building service entrance and on the secondary of any transformer that isolates the primary and secondary windings. The neutral bus in all circuit breaker panels other than those serving as service entrance (typical for residence wiring) must be insulated from the case. It is HIGHLY DESIRABLE to have a circuit breaker panel in the computer room DEDICATED to the circuits in the computer room. Specifications for a computer room circuit breaker panel: 1. The panel should have room for future expansion 2. Input wiring for the panel: - Should originate at the main distribution panel for the building. - There should be a ground wire from the building service entrance ground (or vertical steel beam that is contiguous to earth and part of the building ground)to the panel that is the same size as the supplying conductors. - All available phases should be wired. If three phases are available, all three should be wired into the panel. 3. The panel should contain two ground buses. - An isolated ground bus that is insulated from the case, connected to the service entrance entrance ground, and used for all isolated ground circuits in the computer room. - A ground bus bonded to the panel for all nonisolated ground circuits in the computer room. 4. The neutral bus must be insulated from the case. ORIGINATOR: N. Jones HANDBOOKS-BASIC FOUR-Environmental------------------FIB005 Pg001 FIB 00006 07/14/89 *** Isolated Ground Receptacles and Circuits *** All circuits supplying power to CPUs and critical I/O devices such as disk and . tape drives should be dedicated, isolated ground circuits with isolated ground receptacles. An isolated ground receptacle is normally identified by its orange color or by an orange or white triangle on its face. An isolated ground circuit is defined as follows: 1. It must have three wires dedicated to it dedicated hot dedicated neutral (if a 120V circuit) dedicated ground 2. It must be on a dedicated circuit breaker 3. The three wires must be run in a dedicated conduit 4. The ground wire must be an insulated wire (not a bare wire) which is insulated from conduit and originates at the building service entrance ground (or a vertical steel beam which is contiguous to earth and a part of the building ground). 5. The receptacle must be an isolated ground type of receptacle (I.G.) which insulates the ground wire from the outlet box the receptacle is mounted in. A normal receptacle (non-isolated) ties the ground lug of the receptacle to the outlet box it is mounted in and thus to the conduit. In many cases there will be no ground wire at all and the ground will be provided through the metal conduit. An isolated ground receptacle isolates the ground lug of the receptacle from the outlet it is mounted in and thus is isolated from conduit. An insulated green wire ground is required in isolated ground circuits. ORIGINATOR: N. Jones HANDBOOKS-BASIC FOUR-Environmental------------------FIB006 Pg001 FIB 00007 07/14/89 *** Wire Color Codes and Characteristics *** WIRE COLOR CODES Phase A - black Phase B - red Phase C - blue Neutral - white Ground - green NOTE: The electrical code no longer requires that the wires be color coded, however the standard color codes are still commonly used by electricians. The wires frequently are identified by a few wraps of colored electrical tape. NOTE: MBF line cords DO NOT follow the standard color codes. MBF line cord color codes are: Hot = brown Neutral = light blue Ground = green CHARACTERISTICS OF POPULAR WIRE SIZES WIRE NOMINAL NOMINAL RESISTANCE MAX CONTINUOUS GUAGE BARE CIRCULAR IN OHMS/ CURRENT IN (AWG) DIAMETER MILS 1000 FT CONFINED SPACE (INCHES) @ 20 (AMPS) DEGREES C 0000 0.4600 211600 0.4901 225 000 0.4096 167800 0.06182 200 00 0.3648 133100 0.07793 175 0 0.3249 105600 0.09825 150 1 0.2893 83690 0.1239 125 2 0.2576 66360 0.1563 100 4 0.2043 41740 0.2485 80 6 0.1620 26240 0.3952 60 8 0.1285 16510 0.6281 46 10 0.1019 10380 0.9988 33 12 0.0808 6530 1.59 23 14 0.0641 4110 2.52 17 16 0.0508 2580 4.02 13 Normal wire guages used with common size circuit breakers: 20 amp circuit - No. 12 AWG 30 amp circuit - No. 10 AWG 40 amp circuit - No. 8 AWG NOTE: If a system has to be installed where the wire run from the circuit breaker panel is greater than 45 feet, the wire size should be increased by one size (smaller AWG number) due to the impedence of the wire. This SHOULD NOT OCCUR IF THERE IS A COMPUTER ROOM CIRCUIT BREAKER PANEL IN THE COMPUTER ROOM! ORIGINATOR: N. Jones HANDBOOKS-BASIC FOUR-Environmental------------------FIB007 Pg001 HANDBOOKS-BASIC FOUR-Environmental------------------FIB007 Pg002 FIB 00008 07/14/89 *** Computer Room Circuit Breaker Panel *** |B| |R| |B| _____________________|L|___________|E|___________|L|____________________ | |K| |D| |U| | | _|_|_ _|_|_ _|_|_ | | | | | | | | | | | --- | | --- | | --- | | | |_____| |_____| |_____| | | PHASE A PHASE B PHASE C | | ________________________________________________________________ | | | CIRCUIT BREAKER - PHASE A | CIRCUIT BREAKER - PHASE A | | | |________________________________|_______________________________| | | | CIRCUIT BREAKER - PHASE B | CIRCUIT BREAKER - PHASE B | | | |________________________________|_______________________________| | | | CIRCUIT BREAKER - PHASE C | CIRCUIT BREAKER - PHASE C | | | |________________________________|_______________________________| | | | CIRCUIT BREAKER - PHASE A | CIRCUIT BREAKER - PHASE A | | | |________________________________|_______________________________| | | | CIRCUIT BREAKER - PHASE B | CIRCUIT BREAKER - PHASE B | | | |________________________________|_______________________________| | | | CIRCUIT BREAKER - PHASE C | CIRCUIT BREAKER - PHASE C | | | |________________________________|_______________________________| | | | | | | |W| | | |H| | | _|T|__________________________________________________________ | | | | | | | | --- | NEUTRAL BUS - ISOLATED FROM PANEL | | | |_____|________________________________________________________| | | | | |G| | | |R| | | _|N|__________________________________________________________ | | | | | | | | --- | ISOLATED GROUND BUS - ISOLATED FROM PANEL | | | |_____|________________________________________________________| | | | | | | ______________________________________________________________ | | | | | | | GROUND BUS - BONDED TO PANEL | | | |______________________________________________________________| | | | | | |________________________________________________________________________| The panel should be located in the computer room with all its circuits dedicated to devices in the computer room. The panel should have room for future expansion. HANDBOOKS-BASIC FOUR-Environmental------------------FIB008 Pg001 Input wiring for the panel: 1. Should originate at the main distribution panel for the building. 2. There should be a ground wire from the building service entrance ground (or vertical steel beam that is contiguous to earth and part of the building ground) that is the same size as the supplying conductors. 3. All available phases should be wired. If three phases are available all three phases should be wired into the panel. The panel should contain two ground buses. 1. An isolated ground bus that is insulated from the panel, connected to the service entrance ground, and used for all isolated ground circuits in the computer room. 2. A ground bus bonded to the panel for all non-isolated ground circuits in the computer room. The neutral bus must be isolated from the panel. ORIGINATOR: N. Jones HANDBOOKS-BASIC FOUR-Environmental------------------FIB008 Pg002 FIB 00009 07/14/89 *** Hazardous Use of an Isolated Ground Rod *** PROPERLY GROUNDED CIRCUIT CIRCUIT BREAKER LOAD PANEL DEVICE _________ _______ | | short | | *------HOT-----------o\o---------black-------------*---\ | * | | | / | * | | | \ | * | | | / | * | | | \ | *---+--NEUTRAL-------------------white-----------------/ | | | | | | +--GROUND--------------+-----green--100V >100V >100V II. MODEL 7100 GROUNDCHEK NOTES If wiring conditions are indicated as normal, the 7100 starts pulsing the ground wire with a 7 to 11 amp pulse at a rate of every 3-4 seconds. The pulse duration is 10 to 15 microseconds. The purpose of this test is to check the impedence of the ground path to neutral under a loaded condition. GROUND LAMP MEANING ON BLINKING OFF 7100 GND <2 OHMS GND 2-10 OHMS GND >10 OHMS B7100 GND <1 OHM GND 1-10 OHMS GND >10 OHMS If lamps 1,2 and ground blink simultaneously, the hot wire has >2 OHMS impedence. To use the 7100 for wire tracing with an AC ammeter, the neutral/ground reversal probe (neutral impedence probe No. 7564) is required for tracing the neutral wire. This will cause the pulse to appear on the hot and neutral wires. III. Model 7106 Notes The unit pulses when the red button is depressed. The wire pulsed is controlled by the black button; if OUT, the ground wire is pulsed, if IN, the neutral wire is pulsed. Pulse; 7-11 amps every 3-4 seconds, with a duration of 10 to 15 microseconds. HANDBOOKS-BASIC FOUR-Environmental------------------FIB011 Pg001 The 7106 can be damaged if it pulses with wiring incorrect or if it pulses as it is plugged or unplugged!!! Be sure that the red button is OUT when the 7106 is being plugged or unplugged. The ground impedence test (test No. 5) tests the impedence of the ground path to neutral under a loaded condition (black button OUT, red button IN). GROUND LAMP MEANING IN THE GROUND IMPEDENCE TEST ON BLINKING OFF 7106 GND <2 OHMS GND 2-10 OHMS GND >10 OHMS B7106 GND <1 OHM GND 1-10 OHMS GND >10 OHMS If lamps 1,2, and ground blink simultaneously while the 7106 is pulsing (anytime the red button is IN) the hot wire has >2 OHMS impedence. To use the 7106 or B7106 for wire tracing, use a rubber band to hold the red button IN to keep the unit pulsing. Be sure to remove the rubber band before either unplugging or changing the position of the black button. Wires pulsed are: black button IN - hot and ground black button OUT - hot and neutral The neutral to ground short test (test No. 3) and the isolated ground short test (test No. 10) will in most cases indicate problems that do not exist. * If the receptacles are located close to the circuit breaker panel or the wire size is large (both of these conditions are highly desirable), the 7106 will incorrectly indicate shorts. * The only sure way to verify the correctness of the wiring is to trace the wiring, using an AC ammeter and the 7106 (or 7100). Wire tracing is covered in another place in this handbook. The ground lamp on the 7106 is temperature sensitive and gets more sensitive the older it is. It may take several minutes for it to stabilize. IV. Adapters and Accessories Required 1. ECOS 7564 neutral impedence adapter (reverses neutral & ground) 2. ECOS 7562 isolated ground short probe 3. 7571 L5-15 twist lock adapter (15 amp) 4. 7573 L5-20 twist lock adapter (20 amp) 4. a short extension cord (for tight places) 5. To test the IG6-15 receptacle used by the T-303 removable disk drive two adapters can be made locally. 6-15P 5-15R HOT 1 ----------------HOT GROUND------------+---GROUND +---NEUTRAL HOT 2------------------HOT GROUND-------------+---GROUND +---NEUTRAL ORIGINATOR: N. Jones HANDBOOKS-BASIC FOUR-Environmental------------------FIB011 Pg002 HANDBOOKS-BASIC FOUR-Environmental------------------FIB011 Pg003 FIB 00012 07/14/89 *** Building Wiring Verification *** 1. Special tools required a. ECOS 7106 (or 7100) b. ECOS 7564 neutral impedence adapter (reverses neutral and ground) c. ECOS 7562 isolated ground short probe d. ECOS 7571 L5-15 twist lock adapter (15 amp) e. ECOS 7573 L5-20 twist lock adapter (20 amp) f. a short extension cord (for reaching into tight places) g. two special 6-15 adapters (for 208/240V T-303 circuits) - see 7100 and 7106 FIB in this handbook for details h. a several amp current load (a hair dryer works well) i. clamp on ammeter with several ranges, including a low scale (0-6 amps or lower) Amprobe model RS3 works well. j. gummed labels 2. Verify all receptacles with ECOS 7106 (or 7100) including those used by any I/O device attached to the system. See ECOS 7100 and 7106 FIB in this handbook. All receptacles used by CPU, disk and tape drives should be the isolated ground type. These are usually orange or have an orange triangle on the front. Check both outlets in duplex receptacles, since one of them may be defective even though they share the same wiring. 3. Trace wiring from all critical receptacles (CPU, disk, tape,etc.) using the procedure described in the Wire Tracing FIB in this handbook. Examine J boxes between the receptacles and panel for wire nut connections. These are not good solid connections and really should not be allowed for computer circuits. If possible, have them replaced with AL-CU split bolts. 4. Check for current flowing in conduits into circuit breaker panels. It is important to check all accessable conduits even in other panels, since your I/O gear may be connected to any panel in the building. Check for current flow in conduits by clamping ammeter over the conduits. Label any conduits that show current flow with the number of amps indicated. If current flow is indicated, it may be due to actual current flow in the conduit or imbalanced current flow in the wires inside the conduit. If the current flow is balanced in the wires inside the conduit, (same current flow in hot and neutral), with no actual current flow in the conduit, there will be no reading when clamped over the conduit. If possible clamp over all the wires inside the circuit breaker panel after they exit the conduit, any current reading indicates imbalanced current. Another method of determining if the reading is actual current flowing in the conduit is to short the conduit above the point where the reading is being taken, to an adjacent conduit, with a screwdriver or other large conductor. Then, observe for any change in indicated current. If the reading changes it is actual fault current in the conduit. HANDBOOKS-BASIC FOUR-Environmental------------------FIB012 Pg001 If it is determined that current is flowing in conduits, check circuits for imbalance between hot and neutral wires. If no current is flowing in a neutral that has several amps in its associated hot wire, it should be checked out. 5. Check all screws for tightness in the circuit breaker panel on circuit breakers, neutral bus, and ground bus. Observe wiring for discoloration and melted insulation. Heat may be caused by loose connections or excessive current. Watch out for stranded wires, they usually have only a few strands that are actually connected. Pointed screws have little surface area in contact with wires and loosen easily. Shoulder type screws make a firmer and longer lasting connection. 6. Verify that neutral is not connected to the case of the panel unless it is serving as a service entrance panel (directly connected to the electrical service). 7. Inspect circuit breakers for heat or audible noise. If present, replace the breakers. 8. Determine the type of service in the panel (delta, wye, or single phase). Then verify that the voltages are correct. Refer to Common Tranformer Configurations FIB in this handbook. 9. Check the building service entrance. All connections should be tight. 10. Connect an ac line analyzer to a dedicated circuit and monitor several days. If there are multiple phases connected to CPU and critical I/O devices, each phase should be monitored. 11. Clamp an ammeter over the line cords of CPU and critical I/O devices. If ANY reading exists there is some type of ground fault current flowing through the system and it MUST BE LOCATED AND CORRECTED! ORIGINATOR: N. Jones HANDBOOKS-BASIC FOUR-Environmental------------------FIB012 Pg002 FIB 00013 07/14/89 *** Tracing AC Wiring *** 1. Special tools required a. ECOS 7106 (or 7100) b. ECOS 7564 neutral impedence adapter (reverses neutral and ground) c. ECOS 7571 L5-15 twist lock adapter (15 amp) d. ECOS 7573 L5-20 twist lock adapter (20 amp) e. a short extension cord (for reaching into tight places) f. two special 6-15 adapters (for 208/240V T-303 circuits) - see 7100 and 7106 FIB in this handbook for details g. a several amp current load (a hair dryer works well) h. clamp on ammeter with several ranges, including a low scale (0-6 amps or lower) Amprobe model RS3 works well. i gummed labels 2. Verify receptacles with the ECOS 7106 (or 7100) to check for gross wiring errors. Refer to the ECOS 7100 and 7106 FIB in this handbook. 3. Label receptacles (CPU, disk 1,etc) 4. Print small labels for hot, neutral, ground wires for each receptacle to be traced (CPU H, CPU N, CPU G, etc.). 5. Remove cover from circuit breaker panel. 6. Insert ECOS 7106 into receptacle, push black button in, and using a rubber band hold the red button in (or if using a 7100 use an ECOS 7564 neutral impedence adapter, plug adapter and 7100 into receptacle). The ECOS is now pulsing the hot and neutral wires. The pulse will show up as 1/2 to 1 amp pulse every 3 to 4 seconds. Clip the ammeter on the hot wire at the circuit breaker labeled for the outlet being tested. In most cases the labeling is nonexistant or wrong, so it may require checking many hot wires to find the right one. Once the correct hot wire is found, label it accordingly. Observe that no current is flowing in the wire except when the ECOS is pulsing. Note which conduit the hot wire enters. There should be three wires in the conduit if the circuit under test is a dedicated isolated ground circuit (hot, neutral, and ground). 7. Clip the ammeter on the neutral wire (white wire) that is in the same conduit. Observe that there is no current in the neutral except when the ECOS is pulsing. Observe that the pulse is the same strength as in the hot wire then label the neutral wire. 8. At the receptacle under test, remove the rubber band holding the red switch on the ECOS 7106, set the black switch in the out position, then place the red switch back in with the rubber band holding it in (if using a 7100, remove the 7100 & 7564 neutral impedence adapter, insert the 7100 back into the receptacle). The ECOS is now pulsing the hot and ground wires. 9. At the circuit breaker panel, clip the ammeter on the green wire that is in the previously identified conduit. HANDBOOKS-BASIC FOUR-Environmental------------------FIB013 Pg001 Observe that the pulse is the same strength as in the hot wire and that there is no current flowing except when the ECOS pulses, then label the green wire properly. 10. Repeat steps 6 through 9 for each receptacle. 11. Once the wiring has been identified and any problems corrected by an electrician, the labels should be removed from the wires inside the circuit breaker panel. ****** NOTES ****** o The ECOS will heat up after pulsing for 10 or 20 minutes; therefore try to avoid leaving it pulsing longer than necessary. The 7106 is much more sensitive to this than the 7100. o If when checking neutral or ground wires the pulse does not look the same as in the hot wire, use the high current load (hair dryer, etc.) to load test the wire in question. In all cases the current should be the same as in the hot. If it is not the same, the wire may be shared with another circuit, shorted to conduit, etc., but will require an electrician to to correct. To load test the ground wire, insert the 7564 neutral impedence adapter in the receptacle and plug the load (hair dryer, etc.) into the neutral impedence adapter. The load is then placed between hot and ground. o If you are not sure the pulses are the same amplitude as in the hot wire, clip the ammeter over both the hot wire and wire under test. The pulses should cancel if they are the same size (unless you have both wires carrying current in the same direction in which case the pulses will add instead of cancel). ORIGINATOR: N. Jones HANDBOOKS-BASIC FOUR-Environmental------------------FIB013 Pg002 FIB 00014 MAI COMPANY CONFIDENTIAL 11/14/94 *** AC Line Treatment Device Performance Summary *** The following chart is a summary of performance characteristics for various types of AC line conditioning devices. LEGEND: A = Very Good, B = Good, C = Fair, Blank = None TREATMENT DEVICE | BLACKOUT | VOLTAGE | NORMAL | COMMON | LINE |PROTECTION|VARIATION | MODE | MODE |DISTORTION | |PROTECTION|TRANSIENT |TRANSIENT |PROTECTION | | |PROTECTION|PROTECTION| ------------------------------------------------------------------------------- Transient | | | | | suppressor | | | B | B | multi-stage | | | | | (SEE NOTE 1) | | | | | ------------------------------------------------------------------------------- Isolation | | | | | Transformer | | | C | C | Unshielded | | | | | ------------------------------------------------------------------------------- Super | | | | | Isolation | | | C | A | Transformer | | | | | ------------------------------------------------------------------------------- Line Conditioner | | | | | SCR Tap Switcher | | A | A | A | | | | | | ------------------------------------------------------------------------------- Ferroresonant | | | | | Line Conditioner | | B | A | A | A | | | | | ------------------------------------------------------------------------------- Electronic | | | | | Filter | | | A | A | | | | | | ------------------------------------------------------------------------------- | | | | | Surge Protector | | | | | | | | | | ------------------------------------------------------------------------------- | | | | | Motor Generator | A | A | A | A | A | | | | | ------------------------------------------------------------------------------- Off Line Static | | | | | Uninterruptible | A | | | | Power Source | | | | | ------------------------------------------------------------------------------- On-line Static | | | | | Uninterruptible | A | A | A | A | A Power Source | | | | | ------------------------------------------------------------------------------- On-line Rotary | | | | | Uninterruptible | A | A | A | A | A Power Source | | | | | ------------------------------------------------------------------------------- HANDBOOKS-BASIC FOUR-Environmental------------------FIB014 Pg001 NOTE 1: Transient suppressors vary widely in construction, wires protected, and cost. Generally speaking cheaper equals less protecetion! ORIGINATOR: N. Jones HANDBOOKS-BASIC FOUR-Environmental------------------FIB014 Pg002 FIB 00015 07/14/89 *** Dranetz 606-3 AC Line Analyzer Notes *** I. Power Line Disturbance Definitions The four different types of disturbance measurements are: A. Slow Average - The slow average is the steady state RMS level value based on a 10 second moving average of the monitored voltage. Printout occurs when the slow average becomes greater or less than the previous slow average printout by the amount set in the slow average threshold switch (3, 5, 10,or 15 volts). B. Sag/Surge - The Rms voltage of each AC cycle is compared with the current 10 second slow average steady state RMS value. If their difference becomes greater than the Sag/Surge threshold switch setting (3, 5, 10, or 15 volts), then the number of cycles for which the RMS voltage was continuously above or below the moving slow average by an amount greater then the threshold value is printed out. The RMS voltage of the largest Sag/Surge over one cycle is also recorded. C. Impulse - Transient impulses (spikes) having a duration between .5 and 800 microseconds are continuously monitored on each channel (A, B, and C) of the Dranetz input terminals. The highest peak voltage value measured (excluding the instantaneous AC line voltage) in each two-cycle period will be printed out if it exceeds the voltage value selected by the impulse threshold switch (50, 100, 200, or 400 volts). Note that the impulse is ANY deviation from the sine wave. It may be added to or subtracted from the sine wave. D. Frequency - The frequency of the voltage input is monitored by counting the number of cycles during each second. The A channel is the only channel that is monitored for frequency. Printout of the frequency occurs if it deviates by more than the selected threshold (0.5, 1, or 2 HZ) from the previously printed frequency value. A change in power factor may give a frequency printout also. (continued on next page) HANDBOOKS-BASIC FOUR-Environmental------------------FIB015 Pg001 II. Wiring for Single Phase Monitoring To determine whether impulses are common mode or normal mode, the three input terminals can be connected to the single phase power line as shown below. Note that the case ground connection is not used. AC POWER LINE HOT-------------------------------------------+-----o A-1 | NEUTRAL-------------------------------------+-------o A-2 | | | | | +-----o B-1 | GROUND------------------------------------------+---o B-2 | | | | | +---o C-1 | +-------o C-2 o--+ Case Ground | | ----- --- - Normal mode impulses will be recorded on channel A and on either channel C (if the impulse is on the neutral line) or channel B (if the impulse is on the hot line). Common mode impulses will be recorded on channels B and C. Sags, surges, and slow average changes will not be recorded on channel C (neutral to ground), because the power line analyzer cannot measure steady state voltages below 30-40 volts. Many of the disturbances that are recorded may be neither strictly normal or common mode, but a combination of both (for example, a 100 volt impulse beween hot and dround and a 60 volt impulse between neutral and ground). III. Wiring connections for three phase monitoring 120/208V Grounded Wye Three-Phase System *-----------------Phase A--------------o A2 * A * *-------------+---Neutral---------+----o A1 * * | | C * * B ----- Ground | * * --- | * * - +----o B1 | | | | +----------Phase B---------|----o B2 | | | +----o C1 +-------------------------Phase C--------------o C2 HANDBOOKS-BASIC FOUR-Environmental------------------FIB015 Pg002 Center Tapped Delta Three-Phase System A *---------------Phase A------+----o A1 * * | +--o A2 * * | | * * | | C * * B | | * * * * * * * * * * *-----Phase B------|-+--o B1 | | +--|----o B2 | +----------------Neutral | | | | | | | ----- Ground | | | --- | | | - | | | | +----o C2 +---------------------------Phase C-+-------o C1 IV. Set-up Notes A. When setting the clock, remember the printer is considerably behind the clock especially when using the fast button. It is usually not worthwhile to get the clock set exact, note on the beginning of the tape any clock correction which should be made to a printout. B. Note on the first of the tape the customer name and date for reference. C. Threshold settings for monitoring 120V single phase should be set for minimum values and then if printouts occur too often modify the particular threshold setting as needed. This will allow gathering the most information. ORIGINATOR: N. Jones HANDBOOKS-BASIC FOUR-Environmental------------------FIB015 Pg003 FIB 00016 07/14/89 *** BMI 2400 & 4800 Environmental Monitor Notes *** The BMI 4800 Environmental Monitor has four main AC/DC channels and eight environmental channels for optional environmental probes such as temperature, relative humidity, RFI, etc. The output is a graphics printout of the failure in the form of a scope picture of the event. The BMI 2400 Environmental Monitor has two main AC/DC channels and four environmental channels for optional environmental probes. The graphics printout is smaller (uses narrower paper). It is also somewhat smaller, otherwise it is identical to the 4800. Both of these monitors come with good manuals but in the event a manual is not available, they also have very nice helps built in. If you press the help button anytime you have a question about what to do next your answer will be printed out. Also if you press the help button while answering the type of power to monitor (ex. single phase) the hook-up connections will be printed out. These monitors were designed to have the calibration module swapped out every 12 months, if the calibration module is out of date print-outs will say uncalibrated data and will not include the BMI logo. One way around this temporarily is to set the date a year earlier. Key sequence to lock the keyboard: 1. press LOCK and release 2. press DOWN ARROW and release Key sequence to unlock keyboard: 1. press LOCK and release 2. press CLEAR and release If the monitor is completely hung and will not reset when unplugged and replugged a manual reset can be accomplished by shorting both pins of receptacle marked 10-14 volts in. This is located on rear of unit. A paper clip works well. The main AC/DC channel inputs labeled GROUND are commoned to the monitor's AC input ground. If the monitor's AC input is different from the circuit being monitored and the GROUND inputs are connected, a ground loop exists and may cause erroneous results. It is best to NOT USE the inputs labeled GROUND and merely plug the channel inputs labeled + (plus) and - (minus) as needed (they are the only ones monitored). ORIGINATOR: N. Jones HANDBOOKS-BASIC FOUR-Environmental------------------FIB016 Pg001 FIB 00017 07/24/89 *** Techniques for Protecting RS232 Devices from Transients *** RS232 devices (and their hosts) are very suceptible to damage from transients as this imposes a potential difference between the device and the CPU with resulting damage to the interface drivers and receivers. If there is a thunderstorm nearby there can be several thousand volts potential difference between buildings which are physically close and can have a similar impact on various parts of the same building. The worst case situation is when cables are connected between seperate buildings. It is a virtual certainty that there will be excessive problems when this occurs, therefore the customer should be very well informed of the probability of problems with both the RS232 device and host CPU before the cables are run. WHO NEEDS TRANSIENT PROTECTION Transient protection should be used in the following circumstances: A. On all RS232 cables which exit the building which houses the CPU. B. On cables in excess of 300 feet which are routed through or near building roof support structures. C. On any cable or customer installation where a device repeatedly loses communications ability following storm activity. METHODS OF PROTECTION A. Use proper methods of cable construction and installation: 1. In cases where the RS232 cable must be run between buildings, the cable should be buried a minimum of 18 inches deep in metal conduit. The conduit should be securely grounded to building ground at both ends. NOTE: Anytime an RS232 cable exits the building which houses the CPU, a multistage surge protector must be installed on both ends of the cable. 2. Use shielded cable with the shield grounded to electrical ground. The preferred method is to ground all shields on a ground buss at a common point such as a patch panel and connect the ground buss to building ground with a low impedence conductor. 3. Use twisted pairs, where the alternate wire from each pair is connected to logic ground at both ends of the cable. B. Install data line surge protectors at both ends of the cables. If the cables exit the building, the surge protectors must be multi stage units to handle the higher anticipated current. C. Install fiber optic cable. This option is costly but is 100 percent effective. The cost can be somewhat reduced by MUXing multiple ports onto one cable. D. Install optically isolated local MUX. HANDBOOKS-BASIC FOUR-Environmental------------------FIB017 Pg001 TYPES OF SURGE PROTECTORS All of the surge protectors function in a similar manner, they present an open . to the circuit until their rated voltage is exceeded, then they turn into a virtual short and shunt the energy to ground. A low impedence ground is imperative for these devices to work properly. A. MOV (Metal Oxide Varister): o Voltage sensitive resistive shunt o Repeated operation lowers breakdown level o Three layer construction o Fast responce/slow clamp o Joules rating to reflect survival o High breakdown to clamp ratio o Low cost B. Gas tube: o Inert gas added to control breakdown (sealed air gap) o Night sleeping sickness o Predictable voltage breakdown o Slow response o Breakdown occurs at very high voltage o Device can handle very large current o Performance degrades with repetitions o Moderate cost C. Silicon avalanche diode (somtimes refered to as Transorb): o PN junction diode o Very large junction o Designed to handle surge currents o Tested for surge handling o Fast responce time o Low breakdown to clamp ratio o No repetitive pulse degradation o Moderate cost D. Hybrid or Multi-stage protector: o Combines silicon avalanche diode, gas tube and may contain MOVs (each protective element is considered a stage) o Incorporates advantages and performance of each element o Cost is high when compared to single stage protectors WHAT TYPE OF PROTECTION TO CHOOSE A. In-house cable over 300 feet 1. Use proper cable construction and installation procedures 2. A single stage surge protector should suffice (at both ends of cable) B. External cables (cable leaves building which houses the CPU) 1. Use proper cable construction and installation procedures 2. Install multi-stage surge protectors at both ends of cable 3. Install optically isolated MUX 4. Install fiber optic cable HANDBOOKS-BASIC FOUR-Environmental------------------FIB017 Pg002 SURGE PROTECTION INSTALLATION TECHNIQUES A. In-line RS232 surge protectors (utilizing two DB25 connectors) 1. These devices normally use pin 1 for ground to drain the energy. For proper operation with MBF I/O devices a ground wire MUST be added carrying this ground to AC ground. The best way is to connect to AC ground at the receptacle, a less effective way is to use the pigtail ground insuring that the internal ground jumper inside the device is properly connected. B. Multi-stage surge protectors utilizing screw type terminal strips. These devices are available in 2, 4, 8, & 32 line blocks. 1. These devices require that the cable be cut and the wires inserted under screw type terminals. 2. These devices can be installed in the ceiling or other out of the way location without creating an unsightly mess. 3. The ground lug must be connected to building ground with a low impedence conductor (# 10 wire for multi-cable protector, # 14 wire for single cable protector). 4. All wires which connect end to end in the cable must be protected. 5. The larger devices (32 line for ex.) can be used at the CPU end on SPx, MPx, & ASx systems on patch panels, in cable rooms, or in ceilings allowing for a neat installation. C. Multi-stage surge protectors utilizing punch down terminal strips. 1. The ground lug must be connected to building ground with a low impedence conductor (# 10 wire). 2. These devices are primarily useful on patch panels which utilize twisted pair telco wiring. SOURCE FOR RS232 PROTECTORS At the present time MAI Basic Four supplies does not carry any type of RS232 protectors. One source for devices described in this FIB is Black Box. They may be contacted at (412) 746-5530. Black Box devices are listed below with prices as of 07/13/89, the prices will not be maintained, they are for reference only: o GL-SP152 - $600 - 50 line multi-stage surge protector - punch down terminal strips o GL-SP260 - $390 - 32 line multi-stage surge protector - screw type terminal strips o GL-SP124B - $89 - 4 line multi-stage surge protector - screw type terminal strips o GL-SP128B - $138 - 8 line multi-stage surge protector - screw type terminal strips o GL-SP140B - $48 - in-line single stage surge protector - DB25 connectors o GL-MX612B - $395 - 8 channel optically isolated MUX/local modem o Fiber optic cable, modems, and MUXes also available from Black Box ORIGINATOR: N. Jones/M. Burch HANDBOOKS-BASIC FOUR-Environmental------------------FIB017 Pg003