Operating instructions

TM 11574A-OI

3-32

Figure 3-13. DPRV Replacement Value Chart.

NOTE

This test should not be run below 30 F (-1.1 C) or above 120 F (49 C). If the actual

differential pressure is close to the replacement differential pressure, it is recommended

that the readings be taken several times at two minutes intervals.

If valve cap is found to be leaking it may be replaced using cap & O-ring (Carrier Part Number 40-

50024-00).

(17) Autotransformer

(a) If the Autotransformer unit does not start, check the following:

Make sure the 460 VAC (yellow) power cable is plugged into the receptacle (Figure

TBA, Item 3) and locked in place.

Make sure that circuit breakers CB-1 and CB-2 are in the “ON” position. If the circuit

breakers do not hold in, check voltage supply.

There is no internal protector for this transformer design; therefore, no checking of

the internal protector is required.

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.