Bench Testing Electrical Components

[Tinkerman]

I'm about to rebuild horns, heaters, and wiper motors (I have several of each) and was wondering if any body set up a system to test these components before rebuild, to see if the motors work and if so, how did you do it?

Thanks, Tinkerman

 

[Brosky]

I used one of my 12 volt power supplies from my Ham Radio setup to power anything that needs juice and a digital volt/ohm meter for testing. Several ground straps with alligator clips back to the power supply and all is well for power and testing.

 

[JodyFKerr]

I also recommend, based on the power source for testing, that you add a changeable inline fuse to the alligator clips. Saves you from accidentally overloading anything you test.


Jody

 

[martx-5]

I used a 10 amp battery charger for all of that work.

 

[TR3driver]

Depends on the item. TR3 horns draw a LOT of current, intermittantly (in pulses), so they do not work the same when powered from something like a battery charger that has a relatively high internal resistance. So I don't bother testing them on the bench, beyond continuity; unless I happen to have a charged 12v battery handy.

But heater and wiper motors don't draw nearly as much, so they can be tested with a battery charger. I actually have a 0-50 volt 10 amp power supply with pretty good filtering (discarded by a previous employer) that I keep on the bench for testing.

As long as your power supply is protected, the in-line fuses seem like more of a PITA than they are worth. And if you are using a car battery or similar, the lead itself will act like a fusible link. But that's just my opinion, make up your own mind.

BTW, Radio Shack sells some reasonable quality clip leads for not too much. I carry a few in the car (along with a DMM), just because they come in handy.

 

[martx-5]

The horns on my TR3 sounded off OK using my 10 amp battery charger. I only did one at a time, and just for a short duration to make sure they worked.

 

[Brosky]

I do have fuses on my power supplies and one of them is variable, so I can adjust the power up and down as needed.

 

[poolboy]

I used a 10 amp battery charger for all of that work.

Same here.

 

[Sarastro]

If you look on ebay, you can find some single-voltage power supplies in the 12V range. Some of these are adjustable over a few volt range, and some have ipmpressive output current. And, best of all, they're cheap. 12 volts is a common value, and if the thing is adjustable, you can probably tweak it to ~13V, which is closer to the real voltage of our electrical systems.

I use a second-hand Hewlett-Packard 10-amp adjustable power supply I got on ebay. Wasn't terribly expensive (I think about $100) but more than most people would want to pay for such things. But it's an option.

 

[angelfj1]

I do have fuses on my power supplies and one of them is variable, so I can adjust the power up and down as needed.

Paul: I've been playin' with electricity all my life but
I've never yet seen a variable fuse!

 

[dklawson]

I read Paul's post the same way. I knew what he meant but it still made me smile.

Look over this string of posts. It struck me as interesting that so many of us take our DIY service and repairs so far that we have bench power supplies of various types just for such work. For my work, I have a small surplus 1.5 Amp bench supply for the really small stuff, a variable 3 Amp quality supply for gauges, and I use a battery charger (or battery) for the big stuff.

 

[Brosky]

OK Frank, you got me on my poor verbiage. Good call.

I should have said; I have variable voltage and amperage controls on one of my power supplies, but have in line fuses on both.

 

[angelfj1]

Paul

I'm sorry - the devil made me do it!

 

[Brosky]

No need to be sorry. Upon my reading it over, it does look like I've invented variable fuses.

Oh well, Al Gore invented the internet and Congress is now inventing new jobs, so why not?