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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: aussiesmg on March 10, 2012, 11:12:49 AM

Title: MCI MC5 24v or 12v electricals
Post by: aussiesmg on March 10, 2012, 11:12:49 AM
I have the two batteries wired in sequence on my MC5 but I am wondering what the voltage to the accessories, like the gauges, is? I am doing some upgrades including new gauges and a trailer brake controller so need to know if it is all 24 or 12 volt behind the dash.

Thanks in advance
Title: Re: MCI MC5 24v or 12v electricals
Post by: lostagain on March 10, 2012, 11:34:19 AM
MC5s in stock form are 24 volts. You can easily double check with a volt meter. You can get 12 volts with a Vanner equalizer, or converter, or simply taking from one of the batteries. Some of the members here are, unlike me, very good at everything electrical and will help if needed. Do a search in the archives.

JC
Title: Re: MCI MC5 24v or 12v electricals
Post by: Lin on March 10, 2012, 01:23:39 PM
Mc5's are 24 volt just about everywhere as long as no one has modified it.  As you know, that does happen.  In conversions, most go with a separate 12v system for the house stuff.  There are various ways to do that.  Gauges are available in 24v at prices comparable to 12v ones.  If that is the voltage you have, stick with it as much as possible.  Definitely test with a voltmeter/multimeter before you make any assumptions.  As far as the trailer brake controller goes, I do not know if it comes 24v, but having that as 12v is not a problem either.  The 12v can be drawn from your separate 12v battery bank, using a Vanner equalizer, or center tapping the 24v bank, which is generally not recommended for anything beyond minimal loads.  I seem to remember that there is a 12v lug in the rear junction box too.  I do not remember the number.  The manual should say.  If not, you can use your voltmeter to find it.
Title: Re: MCI MC5 24v or 12v electricals
Post by: thomasinnv on March 10, 2012, 01:25:31 PM
taking 12v from one battery in a 24v system is known as center tapping, and is frowned upon by most, for good reason. this can lead to uneven charging between the 2 batteries.

i guess Lin was posting at the same time.