Engineering Documentation

Table Of Contents
Chapter 1 Wiring Regulations and Specifications
Controlling Transients
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Controlling Transients
Any sensor or communication wiring that is exiting a building must have transient
protection; effective protection requires proper wiring (grounding). Where protection is
needed, use the parts listed in the following table.
MOV Part Numbers.
Part Number Description Application
540-248 MOV (3)60V
Ipk 1200 amp
(25 pack) 3 MOV pre-twisted for use on 24 Vac 3-wire power terminals.
550-809 P10 MOV 60V Ipk 4500A
(10 pack) MOV with ¼-inch spade terminals for use across flow switch power in VAV
boxes.
The parts listed in the following table must be ordered from an external supplier.
MOV Information—Order from an External Supplier.
Description Application
MOV 30V IpK 2000 amp 24 Vac input power for use at transformer with earth grounded secondary neutral.
MOV 60V IpK 1200 amp TEC damper/actuator 24 Vac outputs.
MOV 150V IpK 6500 amp For use across the power line in 102V - 132V applications.
MOV 208 – 250V IpK 1200 amp Termination boards or Controllers with on board digital outputs that do not have MOVs should use this
part across the digital outputs. Not for use across power lines.
Products without digital output MOVs: DXR2, PTM6.2Q250(-M) and TXM1.6R(-M).
Products with digital output MOVs: Compact, ATEC, TEC, BTEC, PTEC
MOV 275V IpK 2500 amp For use across the power line in 180V - 265V applications.
Receptacle Assembly with MOVs Duplex 15A or 20A outlet with three 150V IpK 6500 MOVs configured for 102 - 132V across the line
applications (two line-to-line MOVs and one line-to-earth ground MOV).
Ground Wire 12AWG with captive screw, for connecting 24 Vac neutral from Transformer to grounded enclosure
chassis Protective Earth (PE) “ ” attachment point, or for connecting Equipment Controller “E” or
“GND”, or Field Panel “ ” to enclosure chassis in locations with high levels of electrical noise that
interfere with controller operation.
Network Terminators
Terminate Networks were required using following parts.
Terminator Part Numbers.
Part Number Description Application
550-975P100 3-Wire Network Terminator, Pkg. of 100 The 3-wire network requires a new network terminator. The new terminator is
a 120 ohm 1/2W carbon composition resistor. One terminator must be placed
at each end of the 3-wire network section.
550-974P10
3-Wire Network RS-485 Reference
Terminator, Pkg. of 10
The nodes that use a 3-wire network interface must have the RS-485
reference wire (yellow) of the network cable terminated to EARTH GROUND
at ONE END ONLY through an RS-485 reference terminator.
538-664 PMD Trunk Terminator The 2-wire P2 network terminator is a 120 ohm 1/2W carbon composition
resistor in series with two surge diodes forming a capacitor. One terminator
must be placed at each end of the 2-wire network section.
985-124 499 OHM RESISTOR ASSEMBLY KIT Converts 4 – 20 mA to 2 – 10 V input signal for devices that do not have
current inputs. Consists of 499 Ohm, ½ W, 1% metal film resistor with 4 ½”
18 AWG 300V insulated leads.