Stop solenoid operation

Hi Dave

All it says on all drawings is Stop magnet for the stop. 
I have 2 wires coming from the sensor to the old Tachometer. Will both wire be connected to the new tachometer? I ask since i know from the fishing boat that there are only one wire going from the alternator to the tachometer there. It's just so i know how to connect all this again:-)

Will go offshore later today, so are a bit on/off here, since i will be working nights out there. But will answer during the evening/night.

Regards
Tommy

Hi Tommy
​A stop solenoid is a magnetic device usually with a external spring. The spring holds the stop lever on the fuel pump in the 'run' position. When you press the 'stop' button on the {Dragon} instrument panel power is sent to the solenoid which pulls against the spring moving the lever to the stop position.  When you let go of the stop button the spring returns the lever to the run state.

Note Solenoides can be:
Power in external spring out.
Power in internal spring out.
Power in power out.

Solenoid failure modes are:
Spring broken - engine will not start lever in stop position.
Solenoid fault - engine will not stop (spring type) engine will not stop or engine will not start (power in and out type)

​The {Dragon} panel will have a 5 amp push to make switch for your stop button. Some solenoides need more power than this so will need a relay.

Dave