The Stovebolt Site Forums The Shop Area The Electrical Bay watts on deluxe heater blower and w/s wipers

My project is a 1956 Chevy 3100 with a 235 and a 12v generator. 2 questions (1) how many watts or amps does the deluxe heater blower use while running and (2)how many watts or amps does the windshield wipers use while running? I have looked in the factory build manual and the shop manual and found nothing? It only lists it as an option with dashed lines on the diagrams.

I am doing a load calculation so I may size an alternator with all the accessories that I will add in a future date. I am building my own wiring harness and adding a fuse block with modern fuses. I understand ohm's laws but I just can not find the amps or watts of those two items. I just need the running amps so I get the proper alternator with out too much over kill.

thanks a bunch again

you're over thinking it Jaime, the standard generator was 35 amps, the biggest optional one was 55 amps, don't think you'd even find an alternator that small, but a 60 amp will take care of more electrical stuff than the factory offered .... more important is the fuse size, 9amps for both items - which you'll know is 'overload'

Bill

I am not using the generator I am replacing it with an alternator. The alternator I will be using is an 12 SI Delco with amps size unknown yet. I am adding power door locks, alarm, air conditioning, power windows, power seat, upgrade in lighting with the headlights and LED tail light, towing package, some small lights such as a courtesy lighting in the cab, glove box and under the hood, and a new sound system. Most of these will be options that the truck did not have and I want to be ready as I am adding these upgrades so I do not have to reinvent the wheel again.

I am upgrading the wire size and I have the data on the other electrical components and I would like to know the watts or amps of the original windshield wipers and deluxe heater.

I did not mean to be unclear but since I am not buying a wiring kit. I am making my own harness. I am using the measure twice cut once theory.

So if any one knows the watts or amps plase let me know. I just can not find it in the old car manuals or the manuals I have.

Thanks again sorry for the confusion.

Jaime

I think you have the right idea - get your design right and then put it together.

Totaling load and doing the calcs on paper prior to purchase is the most economical in terms of time and component cost.

Put the unknown loads across 13 or 14 volt and read current. Now you know max current.
Add 10% to the total to ensure you have covered what you may have forgotten.
You may be a bit high when everything comes togeher but underloaded alternators and motors last longer.

if those items take a 9a fuse, you have your max figure if you get a 60 or 80amp alternator, you'll have the minimum size you can get by with, doesn't take any electrical engineering .... look at your list, how much of that will be running at the same time? almost none - if you want some margin for all the bells and whistles, 100amp alternators are fairly common and not much more money

Bill

Yes Leitmotif,
I have front clip off the truck and just started ordering parts for the motor its a complete rebuild. As I was removing the wiring I noticed the majority of the wiring was 20 gauage, a small fuseblock, no fusible links. Since I am redoing everything I decided to do the wiring myself. I bought it out of a field and it had not ran in about 20 years. I work with 460, 240,120, & 24 v circuits ac. Now I am getting proficient with 12v dc. I have no battery yet but since I am taking it down to bare metal I thought it would be a perfect time to upgrade the wiring.

The thing I was hoping for was to get an what the factory watts were and not estimate too high. I could take the12 volts times 9 amps approach to get the max running load amps would be but I know its not accurate I believe gm would not cut it that close or there would be a lot more blown fuses. Since its a motor driven circuit and the start up amps should be different than running amps in theory it would throw my running load calculation off. I know I will not be running everything at once but just wanted an idea.

I forgot to mention I was adding cooling fans to the radiator plus adding relays for those fans and relays for the headlights. I want to keep the majority of the hi amps of what I can outside the cab of at least what I can. Its crazy seeing all the power ran off the ignition and headlight control.

Lastly I am using the 12 volt and watts for the amps to size the wire not the 13 or 14 volt so that should give me my cushion plus I plan to use min of 14 garage wire and bigger since I have a surplus of it.

I guess if there is no info on the factory blower and w/s wipers I will just yank them out and do a bench test. I was hoping someone here would know or where to find it. Those where the only two I did not have.

If anyone one else has any input I would love to hear. Thanks to all.

I could take the 12 volts times 9 amps approach to get the max running load amps would be but I know its not accurate I believe gm would not cut it that close or there would be a lot more blown fuses.

no, GM didn't "cut it close", figuring 9amps gives enough margin that it's highly unlikely the fuse will blow unless there's a major malfunction .... the fuse info is the best you'll find, there is nowhere other than on the motors themselves that the running amperage is specified, so you might try looking there - I've never seen watts referred to anywhere

I'm puzzled that you're adding every possible modern 'amenity' and are concerned about 'overkill' on the alternator, why not get the best you can afford and have that margin of safety??

Bill

Well the answer for the factory wipers is 0 amps because they were vacuum.

A six volt heater blower would draw between 6 and 8 amps.

I think i am getting off on the wrong foot here. I am not here be difficult just wanted to know if anyone knew or know where to find the info at.

As I stated "My project is a 1956 Chevy 3100 with a 235 and a 12v generator." The wipers is not vacuum and its not a 6 volt system. I have a brown wire going to the resister on the firewall.

Bill there is a formula for everything I am just trying to fiqure it out buddy. I just pulled the blower motor out and it stamped 13.5 v and a number of 50477198. I have been googling it and still nothing. Radios & headlight are in watts besides volts x amps is watts. The amps vs volts thing is easy for me to figure out give me one or the other I will be happy, lol. I did not mean to waste anyones time I really did not think it was a stupid question. Not all possible modern 'amenity' will be added now its only that if I plan to install them I want them as an option so I do not have to worry about the alternator or wire size etc. I just do not want to rip thru a wiring harness when i could have planned for it. Thanks again

I doubt anybody here thinks you are being difficult. The discussion is good for everyone.
I'm with Bill BTW, get a 90 or 100 alternator and that will cover anything you might ever have the room in the cab to add.

Jamie, I know there are formulas for everything, and have no doubt you can use them, as can I ..... lighting is rated in watts, radio audio output is rated in watts, motors, as well as the vacuum tubes / transistors and transformers in radios are rated by voltage and amp draw - wire is rated by ampacity ..... I told you above what the fuse ratings were, and that gives you what I thought you were looking for, the max possible draw for those circuits to size the wires and an alternator [rated in amps], I hope you're not looking for the absolute least you can get by on, anything electrical needs a margin of safety .... for what GM has to say about the factory radio see here, for a deluxe heater see here, for the wiper motor see a '57 shop manual [not one online]

Bill

I gave the general draw for a 6 volt heater blower because I happened to know that. Generally speaking, most of the 12 volt accessories draw around half the current of the six volt versions. A radios' output in watts doesn't generally relate closely to the power that the radio uses. If you are going to use a modern radio, you should get some figures provided with the radio.

I thought you sounded competent and qualified.
Your bench test is the final criteria. Dont trust factory specs all the time - they do cut to bare bone to save a nickel on copper. You have seen that in industry - automotive is worse. Oversize wire is always good.

Yeah I also do all that industrial electrical also. 12 VDC is not that different Ohm Law and the rest apply

Thanks guys I will probably get the 100 amp one however I am still curious what the amps or watt's are.

If anyone knows please assist me. Its for my curiosity. If I can not find out I will perform a bench test and post. I am half way there now I just have to pull the wipers.

In the a/c world I get to work on dc buss in variable frequency drives and complexed circuits from 460 to 24 volts. Plus I have been bitten a few times. After 24 years I hope I am a little knowable at least I do not have to wear a flash suit working on my truck.

As any old info in manuals I really do not trust as mistakes and translations and interpretions are made, I was only going to use it as a guide line. Yes definitely I realized that when converted from 6 to 12 volts they could save some pennies on the copper. I have seen "rookie" mishaps because of overloaded and underprotected circuits. On stationary machines I can handle the repair but when I am in traffic with 115 deg f temps I do not want my ride to do the puff the magic dragon show. MAD electric has some great reading info on his web page and I am applying some of his practices on my ride. As far as the amps being lower from a 12 volt system I was aware of the I was not sure if the motor was different because of the year. One thing is for certain after reviewing the circuits in the truck and 2008 car I will only be confident in wiring my truck not too much earlier models. Between here and the shop manual I traced every wire and it really helped to understand the trucks wiring. It really incredible that all the power back then with out fusible links was brought into the cab and energy up into the light switch and ignition switch.



Thanks guys for the input