Product Manual

Table Of Contents

4. Troubleshooting 7-2019

2. Relay K2 energizes, opening K2-11 and K2-12, which removes the run command from the generator

set control.

3. After the retransfer delay, the generator set control de-energizes the relay coil (K1), which closes K1-

1/K1-9 and K1-2/K1-10 and opens K1-7/K1-11 and K1-8/K1-12 to move the transfer switch from the

Generator set position to the Utility position.

4. The S1 auxiliary switch within the transfer switch mechanism breaks the power to the automatic

transfer switch operator coil (C).

5. The load is retransferred to the utility.

6. After a delay to let the engine cool down, the generator set stops.

4.2.3 Troubleshooting with Symptoms

Use the troubleshooting guide to help diagnose transfer switch problems. It is divided into sections based

on the symptom. Common problems are listed with their possible causes. Refer to the corrective action

column for the appropriate test or adjustment procedure. The section in the right column lists the location

of the test or adjustment procedure in the manual.

Always refer to the schematic and wiring diagram package that was shipped with the transfer switch for

specific information about its configuration.

Make a thorough inspection of the transfer switch wiring to make sure that all wires are in good condition

and all connections are made. Correct wiring problems before performing any test or replacing any

components.

4.2.4 Important Troubleshooting Reminders

When troubleshooting the transfer switch, it is important to remember the following:

• This is a two-position transfer switch. It can only be connected to one source. There is no neutral

position and no possibility of paralleling with the utility.

• The generator set control energizes relay coil K1 by supplying a B+ (C13N6H, C17N6H, C20N6H) or

a B- (all other models).

• Terminal Block Jumper (A034N106) provided with model C13N6H, C17N6H, or C20N6H generator

sets is installed between TB4-3 and TB4-4.

• The transfer switch mechanism cannot transfer to a dead source.

• The transfer switch design is intended to signal when utility voltage is not present and when it

returns. The utility sense relay coil will energize or stay energized at voltages other than nominal.

Therefore, the unit should not be expected to signal a failed utility to the generator set during utility

undervoltage or overvoltage conditions.

4.2.5 Troubleshooting for Transfer Switches

For information on the generator set controller fault signals, refer to the generator set service manual. The

tables below list troubleshooting issues for RA Series transfer switches.

WARNING

AC power within the cabinet presents a shock hazard that can cause severe personal injury or

death. Use extreme caution to avoid touching electrical contacts with body, tools, jewelry, hair,

clothes, and etc. Prior to working with live circuits, remove all sources of AC power and remove

power to the door by removing the fuse from the FB fuse block. The following procedures are to

be performed only by technically trained and experienced personnel.