GPIO Output Connection
The 4 outputs are configured as "open drain," enabling direct connection to energize external relays, lamps, or other DC devices.
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It is recommended to use 20-24 AWG wire gauge with the connector. Please note that the OUT GND connection is linked to the CTM-500's supply ground.
GPIO Input Connection
The 4 inputs on the CTM-500 can be configured for monitoring either a digital DC voltage state or an analog DC voltage. All inputs are single-ended.
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Analog input values are sampled and can be reported at a maximum frequency of 10Hz.
Example of Digital Input wiring
For analog voltage monitoring, the measurement range is 0 to +10 volts with a resolution of 10mV. The input can tolerate voltages up to 36 volts. Please note that the IN GND connection is referenced to the CTM-500’s supply ground.
Example of Single Ended Analog Input Wiring
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