I am building a Remote Control for my Fireplace and Fan. I have it completed and working on a Breadboard. I switch the 120VAC Fan with a FORTEK SSR-40 DA and it works fine. I am using a CUON HHG1D-0/032F-20 SR to switch a Low voltage DC on-off circuit that controls the Gas Valve. Forget the wireless RF xmitter and receiver, power supply,etc. it all works.
My problem is... The Gas Valve uses a 520 mV DC current generated by a thermocouple in the pilot light to shift the valve from off to on and turn on the fireplace. It currently uses a wall switch (plain old light switch) to complete the circuit. The DC/DC relay is opto isolated but has 11.4 kohm on-state resistance (At least that's what I think it measures on my DMM) that will not pass enough current to shift the valve. Even putting my DMM in the wall circuit to measure the current output of the thermocouple adds enough resistance to prevent the valve from shifting. This is a very low power application and I need your recommendations on what device I should use for a switch. Input to the DC/DC SSR is 5V DC from a wall wart. It's a low resistance output switch function that's required.
Please note: I'm a component assembler, not a circuit designer. Retired Mechanical Engineers tend to just know enough EE to get into trouble.
My problem is... The Gas Valve uses a 520 mV DC current generated by a thermocouple in the pilot light to shift the valve from off to on and turn on the fireplace. It currently uses a wall switch (plain old light switch) to complete the circuit. The DC/DC relay is opto isolated but has 11.4 kohm on-state resistance (At least that's what I think it measures on my DMM) that will not pass enough current to shift the valve. Even putting my DMM in the wall circuit to measure the current output of the thermocouple adds enough resistance to prevent the valve from shifting. This is a very low power application and I need your recommendations on what device I should use for a switch. Input to the DC/DC SSR is 5V DC from a wall wart. It's a low resistance output switch function that's required.
Please note: I'm a component assembler, not a circuit designer. Retired Mechanical Engineers tend to just know enough EE to get into trouble.