will 24 volt wiper motor run on 12 volt

[robertglines1]

the only two items I need to run on 24 volt is wiper motors and defroster motors...have 12 volt starter and everything else is easy change over...12 to 24 volt converter how many amps do wiper and defroster motors draw? I have extra inverters 12 to 120.could I plug tramsformer in that way?The engine I just bought has a 12v alternator...do I need to change these motors out?  all input apreciated----Bob

[gumpy]

Well, I just installed 12 volt electric wipers in my bus. I had to run a new wire to the front panel because they were drawing around 8 amps surge each motor when on high.

Not sure I'd change them, myself. 24v motors will draw less current than 12v.

[hargreaves]

24 volt wiring  in motors is much smaller than 12 volt motors. They would work but not for long.

[bevans6]

You can use one of these http://store.solar-electric.com/12to24or24to.html to convert 12 volts at 20 amps to 24 volts at 10 amps if that is enough for the wiper motors.  You will need to change out the wiring to the location, since it will not be stout enough to carry the load at 12 volts if designed for 24 volts, but that applies to everything on the bus, all lights, fan motors, wiper motors, relays, etc.  I would never contemplate switching a bus to 12 volts from 24, I would go the other way and create 12 volts to run the engine, and have a 24 volt alternator for the bus.  Unless you are wiring from scratch, obviously.   

I honestly don't know why 24 volt chassis systems aren't more universal on big trucks and such, the benefits would seem to outweigh the cost of an extra battery.  And even that is a benefit once you're paid for it!

Brian

[robertglines1]

.Brian I don't have a 24 volt alternator now.I did howerver get a 12 volt belt driven alternator on the 60 series set up I bought...not using any bus heat and air except drivers unit(2 ton ac).which all I need is blower for this system..I have a 12 volt wiper motor out of a sticks and staples I might try.....thanks for source  ----Gumpy thanks for amp info....after thought I have a extra inverter,could just put a 110 squirel cage in for heat/ac blower in dash..I have several around shop.then would need less 24 volt for what ever...plan on using all 12 volt led on coach:have no taillights at all now,with less amp draw for led tailights it should not overload wires...brake light sensor switch should not know differance?                                                                    

[wrench]

  I think I would look in installing an extra battery & a parallel switch for those 2 circuit.
         wrench

[robertglines1]

will have 2 ea 31 series batt in paralell...could I tap 24 volt off them any way? have tapped 12 off 24 before but never tried other way..not trying to reinvent wheel here but have alt 12V and  have done away with power hogs of the bus ac/heat blowers 24 volt alternators are expensive..and I don't need that much 24 volt power..

[bevans6]

What are you using for defroster blowers and the motors for the driver's AC?  I guess the whole point, which you obviously know, is that the bus wiring is sized for 24 volt and if you switch to 12 volt you have to either replace it, double it up, or find motors  and loads that draw half the wattage.  For me, spending a few hundred bucks on a new alternator would be the easy way out, but to each their own.  You will have to change all the light bulbs on the bus, for example, and the wiring to them will be undersized for the wattage of the 12 volt bulbs unless you go to LED's, which would be a useful upgrade for running lights anyway.

that converter is actually a kind of neat little box.  It is also an equalizer, and it either doubles or halves the input voltage depending on if you set it up as a 12 to 24 volt converter or a 24 volt to 12 volt converter.  I use one to power my trailer lights at 12 volts.

If you don't need much current, 24 volt alternators are available quite cheaply, here are two under $95:

http://compare.ebay.com/like/390203692786?ltyp=AllFixedPriceItemTypes
http://www.amazon.com/dp/B002GD20XE/ref=asc_df_B002GD20XE1159886?smid=A13H5QHGBAEUYH&tag=dealtmp416755-20&linkCode=asn&creative=380341&creativeASIN=B002GD20XE
Brian

[belfert]

I don't know for sure, but I would guess that Robert's bus is new enough to use 12 volt exterior lighting.  My bus is a 1995 and it is 24 volt, but they used a Vanner Equalizer to supply 12 volts for exterior lighting and other 12 volt needs.  Strangely, they still used 24 volts for the interior lighting, engine bay, and luggage bays.

[robertglines1]

I have room for 24 volt alt on motor..maybe will do that with 2 small batteries for 24 volt needs...all coach lighting is or will be 12 volt...98 XLE prevost...good source on 24 volt alternator...Thanks

[bobofthenorth]

If I had 24 volts available my highest priority would be a 24 volt starter.