Go Down

Topic: Old UPS stopped working (Read 1 time) previous topic - next topic

Marciokoko

So I opened up this old UPS because I decided to use the battery for a small solenoid project.

I noticed the UPS has some irlb.4132 which I could use.  But I remember someone warned me about opening these things because they can store charge in capacitors.

So I want to be careful.  What's the best way to discharge the capacitors so I don't get shocked?

A rubber glove and a metal rod connected to a metal surface which is grounded?

AWOL

Don't forget eye protection.
"Pete, it's a fool (who) looks for logic in the chambers of the human heart." Ulysses Everett McGill.
Do not send technical questions via personal messaging - they will be ignored.
I speak for myself, not Arduino.

Marciokoko

Thanks awol.  But is my idea ok or is there a better way?

jremington

The UPS probably stopped working because the battery won't charge, and is now useless.

Marciokoko

The UPS stopped working because the battery will not retain its charge under load.  But the electronics are fine.  Id like to use what I can. 

jremington

#5
May 14, 2016, 09:28 pm Last Edit: May 14, 2016, 09:30 pm by jremington
So I opened up this old UPS because I decided to use the battery for a small solenoid project.
Why do you mislead the forum?

Marciokoko


MarkT

#7
May 14, 2016, 10:41 pm Last Edit: May 14, 2016, 10:41 pm by MarkT
A 1k ohm resistor on a grounded lead.  Don't short a large electrolytic cap unnecessarily, the rest of
the circuit might be damaged, and you might spot-weld the metal rod onto the terminals.

Rubber gloves are not rated as insulated gloves, use an insulated probe like a multimeter probe.

Check the voltage with a multimeter anyway.

In practice if its been days since it was powered up its unlikely to have a stored charge, but
that doesn't mean it cannot, so do test/discharge.
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

Paul__B

Rubber gloves are not rated as insulated gloves, use an insulated probe like a multimeter probe.
Mind you they are used as such during surgery and are pretty reliable I must say!

In practice if its been days since it was powered up its unlikely to have a stored charge, but that doesn't mean it cannot, so do test/discharge.
A couple of days ago I was fascinated to plug the Welch Allyn power supply ("wall wart") into the charger base for a handpiece before plugging it into the mains and was fascinated to see the charge indicator come up for a second or two!  This was after at least two or three days in transit.  Clearly if you make genuine professional equipment you use good parts.

ChrisTenone

Why is it misleading?
Cause you said, "I decided to use the battery for a small solenoid project". Then you said, "the battery will not retain its charge". Folks had to switch gears from thinking about the battery to general salvage. Subtly changing the topic causes confusion when used in a text-only medium such as this forum.
What, I need to say something else too?

Marciokoko

Ok I understand.

But I am trying to do both.

1.  I want to save the mosfets.

2.  I am actually using the battery for the solenoid project.

ChrisTenone

Oh that's fine, I was just explaining the source of confusion.
What, I need to say something else too?

TomGeorge

Hi,
A 1k ohm resistor on a grounded lead.  Don't short a large electrolytic cap unnecessarily, the rest of
the circuit might be damaged, and you might spot-weld the metal rod onto the terminals.

Rubber gloves are not rated as insulated gloves, use an insulated probe like a multimeter probe.

Check the voltage with a multimeter anyway.

In practice if its been days since it was powered up its unlikely to have a stored charge, but
that doesn't mean it cannot, so do test/discharge.
I agree,use a multimeter in DC, and check each cap you suspect.
Tom... :)
Everything runs on smoke, let the smoke out, it stops running....

Go Up