Test of Accelerating Control Potentiometer

2-5. Test of Accelerating Control Potentiometer

With the accelerating control depressed to the

Operation of the potentiometer can be checked without

top SCR speed position (switch ASA2 just ready to

disassembling the control. Proceed as follows:

close), the resistance reading should be 200 ohms or

less.

Disconnect battery and disconnect wire 29A

from either the thermal protector TP or the SCR

e. The resistance between either wire 29A or 13A

terminal board (fig. 2-2 and 2-3).

to the truck frame should be 1 megohm or higher.

Connect ohmmeter from wire 29A and wire

f. If any of the resistance tests are unsatisfactory

13A negative and set meter to the RX100 range.

the accelerating control should be disassembled and

adjusted or repaired as indicated (para 104 and 105).

With the accelerating control depressed to the

creep speed position (switch ASA1 just actuated), the

resistance reading should be between 3,500 and 6,600

2-6. Test of Rectifiers 3 REC and 4 REC

ohms.

These two diode rectifiers are identical. Before

Figure 2-3. Control and SCR panel.

2-9