Return to Section TOC
Return to Master TOC
TROUBLESHOOTING AND REPAIR |
CONTROL TRANSFORMER TEST (continued)
FIGURE F.12 - CONTROL TRANSFORMER
Return to Section TOC
Return to Master TOC
Secondary | Control |
Thermostat | Transformer |
Power |
|
Switch |
|
H2, H3 or H4 (see Input Diagram)
L3 T3
L2 T2
L1 T1
H1
Return to Section TOC
Return to Section TOC
Return to Master TOC
Return to Master TOC
PROCEDURE
1.With the Input Power OFF, remove the case top, right side panel and the input access door. The Control Transformer is located on the back of the Input Box. See Figure F.12.
•The Primary Leads (black)are routed through the Input Box and two of them (depending on input voltage) are connected to L1 and L3 of the Input Contactor. Any unused leads are to be insulated and taped.
•The Secondary leads (red) are connected to the Power Switch (X1) and the Secondary Thermostat (X2).
2.Connect the Input Power and make certain that rated voltage is present at L1 and L3.
NOTE: The
WARNING
ELECTRIC SHOCK can kill.
• Do not touch electrically hot parts.
3.Measure the voltage from X1 to X2. It should be approximately 120VAC.
4.If this reading is incorrect check the connections on the Primary and Secondary lads. If OK, the trans- former may be defective.
NOTE: Common causes of control transformer failure are;
•Improper connection of the Primary leads.
•A defective (shorted) Input Contactor coil.
IMPORTANT
Before installing a new transformer perform the Input Contactor Test.
Carefully read and follow the Input Connection instructions located on the Input Access Door when installing the new transformer. If you do not have those instructions, call The Lincoln Electric Co.
