kgwortman
Machine specs:
Model:   5872, 14kw, 16 circuit panel
Serial number:  6161716
Fuel:  LP
Hours: 244
Install date:  July 2011
Nexus controller

Quick question .... I'm replacing my genset battery and was going to set the control panel switch to off, pull the 7.5 amp controller fuse, and throw the genset breaker before removing the old battery.    For my Nexus controller ...... Do I need to disconnect the battery charger?  Does pulling the 7.5 amp fuse disconnect the battery charger?   If pulling the 7.5 amp fuse does not disconnect the battery charger, then how do I disconnect the charger, if I even need to, before removing the old battery and installing the new?   Do I have to disconnect the battery charger?   I'm an electrical novice, so go easy on me.

I'll remove the negative terminal first and reconnect it first with the new battery install and I plan to wrap the cable connections in non-conductive cloth covers immediately upon removal to avoid any metal contact while I remove the old and install the new.    Thoughts?
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restosud
switch gen off,turn mlcb off,pull fuse and disconnect ground cable first.
install new battery and connect the + cable first,then - cable,plug fuse back in,turn mlcb back on and switch nexus controller to auto again.
check your clock and exercise day/time and you're done.
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Peddler
You do not need to do any of those things to change the battery.  Simply turn the unit to off and replace the battery using good standard practices that any mechanic would use.  The only reason you should turn the unit to off is the unlikely event that the power failed and it tried to start while you were making the connection.  Don't over complicate a very simple procedure. 
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Grady22
Generac puts a label on the battery cable stating that the negative cable needs to be removed first and installed last, as restosud says. I'd think that would be the minimum you'd want to do.
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Cobranut
I agree with Peddler.  Always disconnect a battery ground cable first, and connect it last.
That prevents a short circuit, and a possible battery explosion, if your wrench touches metal while working on the positive terminal.
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kgwortman
Got it.  Thanks for the advice.  I may be overthinking this a bit but, I don’t want to screw anything up.  Wet cell batteries make me very cautious.  
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Cobranut
kgwortman wrote:
Got it.  Thanks for the advice.  I may be overthinking this a bit but, I don’t want to screw anything up.  Wet cell batteries make me very cautious.  


That's a good thing.  I've seen one explode, and you don't want to be near it when that happens.
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