Data Sheet

Use of Safety Contactor for Critical Applications

SDC3260 Motor Controller Datasheet 5

Note 5: Connect the controller’s bottom plate to a wire connected to the Earth while the

charger is plugged in the AC main, or if the controller is powered by an AC power supply.

Note 6: Beware not to create a path from the ground pins on the I/O connector and the

battery minus terminal.

Use of Safety Contactor for Critical Applications

An external safety contactor must be used in any application where damage to property

or injury to person can occur because of uncontrolled motor operation resulting from fail-

ure in the controller’s power output stage.

FIGURE 3. Contactor Wiring Diagram

The contactor coil must be connected to a digital output conﬁgured to activate when

“No MOSFET Failure”. The controller will automatically deactivate the coil if the output is

expected to be off and battery current of 1A or more is measured for more than 0.5s. This

circuit will not protect against other sources of failure such as those described in the “Im-

portant Safety Disclaimer” on Page3.

Controller Mounting

During motor operation, the controller will generate heat that must be dissipated. The

published amps rating can only be fully achieved if adequate cooling is provided. Good

conduction cooling can be achieved by mounting the controller to a metallic surface, such

as the chassis, cabinet, etc.

PwrCtrl

SW1 Main

On/Off Switch 1A

Diode

>20A

Resistor

1K, 0.5W

I/O Connector

VMot

to +40V Max

Digital Out

Ground

Main

Battery

FIGURE 1.Contactor wiring diagram