12
VAV-SVX01C-EN
UCM 4.2 Installation and Wiring
Chapter Overview
This chapter contains information about the following:
•
UCM 4.2 Power Wiring
•
Zone Sensor Wiring
•
Communication Wiring
•
DIP Switch Settings Selection
UCM 4.2 Power Wiring
Power Requirements
WARNING
Hazardous Voltage!
Disconnect all electric power, including remote disconnects before servicing. Follow proper
lockout/tagout procedures to ensure the power can not be inadvertently energized. Failure to
disconnect power before servicing could result in death or serious injury.
WARNING
Electrocution and Fire Hazards with Improperly Installed and Grounded
Field Wiring!
Improperly installed and grounded field wiring poses FIRE & ELECTROCUTION hazards. To avoid
these hazards, you MUST follow requirements for field wiring installation and grounding as
described in the National Electrical Codes (NEC) and your local/state electrical codes. All field
wiring MUST be performed by qualified personnel.
Failure to follow these requirements could result in death or serious injury.
NOTICE
Use Copper Conductors Only!
Unit terminals are not designed to accept other types of conductors. Failure to use copper
conductors could result in equipment damage.
Use at least 16 AWG for power wiring and connect to terminal TB1-1 (+) and TB1-2 (-). 24 VAC is
required to power the UCM control and has an acceptable voltage tolerance of 20 to 28 VAC.
Replace the UCM control box cover after field wiring to prevent any electromagnetic interference.
Note:
A dedicated 24 VAC, 50VA NEC class 2 transformer is recommended to power the UCM.
When powering multiple UCM’s from one transformer, polarity must be maintained.
Terminal TB1-1 is designated positive (+) and terminal TB1-2 is negative (-) to the unit casing
ground.
The power consumption for cooling only Series F Models (VariTrac and VariTrane) is 12 VA (4 VA
for the air valve/actuator and 8 VA for the board). To determine the total UCM power requirement,
add the power consumption per stage to the circuit board power requirement. For example, a
Series F unit containing magnetic contactors with three stages of reheat would consume 42 VA.
Table 4.
VA rating for components
Style
Volt Amps
F - Style Actuator
4 VA
Air Valve Actuator C through E Style
12 VA
Varitrac Actuator
3 VA
Summary of Contents for VAV-UCM 4.2
Page 1: ...May 2010 VAV SVX01C EN Installation Operation Maintenance VAV UCM 4 2...
Page 81: ...VAV SVX01C EN 81 Troubleshooting Figure 46 Single duct with single phase voltage electric heat...
Page 82: ...82 VAV SVX01C EN Troubleshooting Figure 47 Single duct with three phase voltage electric heat...
