EMS-220 Voltage Monitoring Question

[rfazio1951]

I want to get the 12 volt source for pin 1 on the EMS-220 from my battery buss. This because it might be the only thing on in case of alternator failure. But this would mean the voltage to pin 1 of the DB37 connector would be on all the time. Is this ok? Would it put a drain on my battery?

 

[dynonsupport]

It's Ok to have 12V on this pin all the time. It will not drain your battery.

 

[rfazio1951]

Perfect, thanks.

 

[Bubblehead]

Should pin one use a fusible link at the voltage source being measured? I am thinking that a fusible link is suggested for the sensing wires going to the ammeter shunt, perhaps this wire for measuring voltage should also have some protection.

 

[dynonsupport]

The ammeter shunt wires need fuses or fusible links because they are effectively connected directly to the battery with no fuse. Thus if one of these 22 gauge wires was to ground out, it would catch on fire for sure without a fuse.

Most people install the input to the EMS voltage monitor somewhere much more downstream in the electric system, where it tends to be after a fuse. In this case one is not needed. If you are connecting it directly to the battery, then one is needed.

Basically, same rule as anywhere else: Fuses protect wires, so you need a fuse small enough for all downstream wires.

 

[bruceh]

Where is a good place to pick up voltage with the VP-X? I was planning to take it from where the big input wire is on the VP-X.

Would a 26AWG fusible link be advised in this location?

 

[dynonsupport]

When using a VP-X you usually just use the VP-X voltage and don't wire the EMS.

If you really want to use it, I'd hook it to the same output that powers the SkyView.