# Generac Standby Generator won't stay charged



## kdrymer (Jun 12, 2015)

Hello - I have a Generac Centurion 10KW standby generator system with the Nexus controller and a Service Rated Generac Automatic Transfer Switch (ATS). Since we moved into the home about a year ago we noticed that the 12 volt battery within the generator enclosure had a trickle charger connected to the battery terminals and was keeping the battery charged via an extension cord. 

After doing some research I learned that the Nexus controller has a built in battery charger and using the external battery charger is unnecessary. However after disconnecting the external trickle charger I noticed that after a couple days the "Low Battery" alarm message displayed on the controller.

From what I found online there is a T1 wire that is supposed to supply voltage to the controller to charge the battery and after looking at the connections on the Transfer Switch and the Generator, it appears that there may be a wire missing.

In the attached pictures I have highlighted in red the connection I suspect is what is missing but I wanted to have confirmation about this. There is a blue wire connecting into the bottom of the T1 Load terminal, however I do not see any white wires connected through the screw terminal like the other connections have. On the generator picture, you can see there is a wire missing for the "T1 120VAC LOAD SUPPLY" connection. Do I need to have a wire connected from this connection to the connection highlighted on the transfer switch?


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## Dan N. (Jul 23, 2015)

*You are correct*

You will need that T1 wire from the transfer switch to the Generator, as you have pictured. The Model and Serial number would be helpful, but I believe they all have the same concept for the T1 fuse. 

I had a 14 KW Generac with the prewired transfer switch for 3 years then upgraded to a 22KW with the 20 amp whole house transfer switch,

Both hooks ups have the T1 in the transfer switch that run to the T1 connection on the generator and that is what gives your built in charger the power to charge your battery.

T1 supplies 120VAC directly to the charging system. Use a voltmeter and check for 120 Volts AC to neutral (or ground) on each side of the T1 fuse.


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