11.5 Current Limit Trimpot (CL) –
The CL Trimpot sets the current limit
(overload), which limits the maximum current (torque) to the motor. The CL
also limits the AC line inrush current to a safe level during startup. The CL
Trimpot is factory set to 1.5 times the full load rating of the motor. To
increase the current limit, rotate the CL Trimpot clockwise
(do not
exceed 2 times motor current rating (maximum clockwise position))
.
To decrease the current limit, rotate the CL Trimpot counterclockwise.
See Figure 18.
Note:
The correct value Plug-In Horsepower Resistor® must be installed for the CL to operate properly.
Calibration of the CL Trimpot is normally not required when the proper Plug-In Horsepower Resistor® is
installed.
To Recalibrate the CL Trimpot:
1
Disconnect the AC power and wire a DC ammeter in series with either motor armature lead.
Note:
If only an AC ammeter is available, wire it in series with either AC line input lead.
2
Set the Main Speed Potentiometer to approximately 30 - 50 % clockwise position.
3
Set the CL Trimpot fully counterclockwise. The CL LED will illuminate red.
4
Lock the motor shaft (be sure the CL Trimpot is set fully counterclockwise).
5
Apply power and rotate the CL Trimpot clockwise until the desired current reading is observed on the DC
ammeter. Factory Current Limit setting is 1.5 times the full load rating of the motor (with a DC ammeter
26
Warning! If possible, do not adjust trimpots with the main power applied. If adjustments are
made with the main power applied, an insulated adjustment tool must be used and safety
glasses must be worn. High voltage exists in this control. Electrocution can result if caution is not exer-
cised. Safety Warning, on page 6, must be read and understood before proceeding.
!
(Factory set to 150 % of Full Load)
0
200
150
FIGURE 18
CL TRIMPOT RANGE
