7–23
T-340
7.22 Autotransformer
If the unit does not start, check the following:
1. Verify the 460 VAC (yellow) power cable is plugged into the receptacle (see
) and locked in place.
2. Verify that circuit breakers CB-1 and CB-2 are in the “ON” position. If the circuit breakers do not hold in, check
voltage supply.
3. There is no internal protector for this transformer design. So, no checking of the internal protector is required.
4. Using a voltmeter, and with the primary supply circuit ON, check the primary (input) voltage (460 VAC). Next,
check the secondary (output) voltage (230 VAC). The transformer is defective if output voltage is not available.
Figure 7.15 Autotransformer
1) Dual Voltage Modular Autotransformer
2) Circuit Breaker (CB-2) 230-Volt
3) 460 VAC Power Receptacle
- - - - -
Table 7–1 Valve Override Control Displays
Left Display
Controller Communications Codes
(Right Display)
Setting Codes (Right Display)
Cd 41/SELCt
tIM
(Override Timer)
0 00
(0 minutes/0 Seconds)
In 30 second increments to
5 00
(5 minutes/ 0 seconds)
PCnt
(% Setting - DUV Capacity Modulation)
AUtO
(Normal Machinery Control)
0
3
6
10
25
50
100
EEV
(% Setting - Electronic Expansion Valve)
AUtO
(Normal Machinery Control)
CLOSE
(Closed)
0
3
6
10
25
50
100
CAP
(Capacity Mode)
AUtO
(Normal Control)
Std
UnLd
(Economizer = Closed)
ECOn
(Economizer = Open)
