Borel Wiring Question

I’m wiring the Borel twin exhaust gas temp alarm and flybridge remote I received for Christmas and would like to know how others have handled the power supply.

The instructions say “Connect 12VDC to any positive supply that is powered while engine is in operation.” For any of you that have a Borel system, did you take power off the ignition switch . . . or where?

I’m thinking of using a 12-VDC source that I normally switch on at the panel while the engines are running but are not part of the ignition circuitry. There is also the option of an always-on DC source that is available whether the engines are running or not, but that would involve long, difficult wire runs.

Also, I normally fuse any power supply. In this case, however, I would guess any fuse failure would go unnoticed and defeat the purpose of the alarm. What is the consensus on fusing an alarm circuit when it is only energized if the temp sensor set point is exceeded (167F)? When energized it’s supposed to see 20 mA, not to exceed .5 amps.

Thanks in advance.

It only draws enough amps to light an led when at idle so you can wire it just about any way you want. I wired mine to the main battery switch not the ignition circuit. I fuse everything just in case.

Arc said:

It only draws enough amps to light an led when at idle so you can wire it just about any way you want. I wired mine to the main battery switch not the ignition circuit. I fuse everything just in case.

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Thanks. Is yours a Borel? My instructions say no current passes unless the circuit closes. Then it’s LEDs and two horns.

I wired my Borel to the panel's instrument power source which is the same as the "ignition" source. There is no need to fuse it since the source is protected by a breaker.

The Borel's sensor is on the ground side of the alarm so that when a sensor's contacts close it shunts the circuit to ground and allows current to flow in the alarm.

David

DavidM said:

I wired my Borel to the panel's instrument power source which is the same as the "ignition" source. There is no need to fuse it since the source is protected by a breaker.

The Borel's sensor is on the ground side of the alarm so that when a sensor's contacts close it shunts the circuit to ground and allows current to flow in the alarm.

David

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Thanks, David.

I’m probably over-thinking this, as usual. For twins, it seems if the engine (ignition source) providing the power is down for any reason so is the alarm system?

I have 3 exhaust temp sensors, 2 water in fuel and 2 high water sensors in my Borel system. If I hooked it to the ignition then the high water alarms would be off unless the engines are running. I hooked mine to a breaker on the flybridge power panel so I can leave it powered up all the time if I want to. I just hooked up the first WIF sensor because I just installed a new 900MA Racor on the port side. Next year I will replace the 900FG on the starboard side with a 900MA and will hook up the WIF on the starboard side then.

angus99 said:

Thanks, David.

I’m probably over-thinking this, as usual. For twins, it seems if the engine (ignition source) providing the power is down for any reason so is the alarm system?

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Not sure why it is specific to twins, but yes when ignition is down (due to loss of power) the alarm won't work. But if you lose all instruments shouldn't this be a big warning to do something, irrespective of the Borel alarm.


David

DavidM said:

Not sure why it is specific to twins, but yes when ignition is down (due to loss of power) the alarm won't work. But if you lose all instruments shouldn't this be a big warning to do something, irrespective of the Borel alarm.


David

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My scenario was one engine/instrumentation set down—the one powering the Borel—leaving the other unmonitored as I limp back to port. Like I said: over-thinking .

angus99 said:

My scenario was one engine/instrumentation set down—the one powering the Borel—leaving the other unmonitored as I limp back to port. Like I said: over-thinking .

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Add a couple of 5 amp diodes and wire the Borel to both engines. But yes, while limping home hopefully your eyes will be on the temp gauge as well.



David

DavidM said:

Add a couple of 5 amp diodes and wire the Borel to both engines. But yes, while limping home hopefully your eyes will be on the temp gauge as well.

David

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Yes this. It also provides a common "Always On if Either Engine Is Running" power source for other systems if needed.