Twoskinsoneman
Senior Member
- Location
- West Virginia, USA NEC: 2020
- Occupation
- Facility Senior Electrician
Recently there was a new water source and main valve added to our fire pump.
Both valves are normally open and the fire pump can draw from both sources simultaneously. Also either valve can be closed for periodic maintenance of that water source and still leave the system up, with the fire pump supplied by the other source.
The original valve has an OSYSU tamper switch on it that is NO when the valve is fully open. If the valve is less than fully open the switch closes causing a valve tamper alert.
The idea is to add a OSYSU tamper switch to the new valve wired in series with the original valve. Then as long as one of the two valves is fully open the valve tamper alert will not happen.
Assuming that is a dandy idea my issue is that the original OSYSU switch has an 3.5k End Of Line Resistor across its open contacts to monitor the wiring.
What will work? If I put a 3.5k across the new tamper switches' contacts so I've got 7k in the series circuit will it still function do you think?
Both valves are normally open and the fire pump can draw from both sources simultaneously. Also either valve can be closed for periodic maintenance of that water source and still leave the system up, with the fire pump supplied by the other source.
The original valve has an OSYSU tamper switch on it that is NO when the valve is fully open. If the valve is less than fully open the switch closes causing a valve tamper alert.
The idea is to add a OSYSU tamper switch to the new valve wired in series with the original valve. Then as long as one of the two valves is fully open the valve tamper alert will not happen.
Assuming that is a dandy idea my issue is that the original OSYSU switch has an 3.5k End Of Line Resistor across its open contacts to monitor the wiring.
What will work? If I put a 3.5k across the new tamper switches' contacts so I've got 7k in the series circuit will it still function do you think?
