PLUS+1 User Forum

PLUS+1™ Hardware => Controllers => Topic started by: pinias on January 21, 2012, 08:18:23 PM

Title: MC050-010 ISSUE
Post by: pinias on January 21, 2012, 08:18:23 PM
Hello there,

I would like to know if someone has had the following issue:

I have a MC050-010 controller that process some signals and triggers some solid state relays (SSR). The SSR are PWM driven by the controller.

The controller only drives the SSR if the user wants to power on/off a pump.
The controller  drives another SSR for engine shutdown. In this case the SSR triggers a selenoid to close an ENGINE AIRSHUT OFF valve.This must happen only if some conditions are true.
the issue is as follows:
When I power off the system (controller and display and some other hardware) and the voltage drops about 4-5 volts I can see that the controller triggers the SSR for about 1 second. For pump purposes it is not a big deal nothing happens, however for engine shut down it is a big deal because the airshut off valve is activated (closed) and remains in this state even by removing the power so it has to be opened manually.

does someone knows how to avoid this situation?

I mean how to avoid the MF output  of the controller supplies voltage to the SSR while powering off.

I appreciate