HP-IL ATC-00010 Relay Actuator revisted

[Sylvain Cote]

There had been a lot of questions on this device over time and no definitive answer was provided.
So, when I was able to buy one, I did. After two hours of exploration I was able to completely understand this simple device.
To my knowledge, the AirTherm Corporation is/was a HVAC company. So I assume the unit was use to control HVAC 12v equipment.
But your guest is as good as mine.
Best regards,
Sylvain