Technical information

2 – CONTROL CARD
9
2.1 Control Card Setup
2.1.1 CT Ratio Scaling
The motor current signal scaling is set according to the motor size and the application specified when the starter is ordered. To
ensure accurate operation, the motor current signal must be correctly scaled for the motor (and its application) being controlled by the
starter. Motor current signal scaling may have to be changed if:
• Motor size has been changed from the original specification.
• Motor load has been changed from the original application.
Motor current signal scaling is accomplished by verifying the current transformer ratio as supplied with the starter and then selecting
the correct DIP switch setting from the chart on the following page for the current transformer ratio. The DIP switches are:
Figure 2 – CT Inputs and CT switches
• ON in the RIGHT position
• OFF in the LEFT position
• Refer to for Figure 1 – Control Card Layout
actual location of switches
NOTE: The applicable ratio is stamped on each CT. Adjust the DIP switches only when there is no current being supplied to the
motor, or the switches could be damaged.
NOTE: See the CT Ratio parameter on page 83.
2.1.2 CT Polarity
The CT has a polarity that must be correct for the starter to correctly measure Watts, kW Hours, Power Factor, and for the Power and
TruTorque motor control functions to operate properly.
Each CT has a dot on one side of the flat surfaces. This dot, normally white in color, must be facing in the direction of the line.
The CT can be placed either before or after the starter. In specific applications, like Inside Delta and a starter with a DC brake, the
CTs must be before the starter.
CT1 must be on Line L1 (R), CT2 must be on Line L2 (S), and CT3 must be on Line L3 (T).
2.1.3 Confirm Switch Settings
To verify or change the motor current signal scaling:
• Compare the CT ratio stamped on each CT to the CT ratio listed on the wiring diagram supplied with the starter to ensure the
correct CTs are installed.
• Inspect the control card to ensure that the DIP switches are in the correct positions for the applicable CT ratio and the motor
full-load Amps (FLA).
CT Input, White wire (+)
CT Input Black wire (-)