Bench power supply (question)

[Magic_x_uk]

Hi

Wanting to get one of these bench power supplies that you can pick up quite cheap

For powering my chargers that I use to charge batteries for RC flying.

I have a 12v psu, but the chargers can perform better on 18 - 32v

Now on the these bench psu's.
I understand what changing the output voltage does

But they also have Amp outputs that you can change. Which I don't understand. Do I just want to give my chargers lots of amps?

As the specs for the chargers just mention input voltage eg- 12-18v / 12v-32v


Thanks

Just don't understand the Amp bit

 

[Diddums]

@Feek is probably the man for this.

 

[BUDFORCE]

Is this to charge LIPOs?

Usually you charge at the same voltage as the battery and you can set the amps to charge, most recommend at "1c".

So a 5000mah battery you could charge at 5amps.

1000mah at 1amp etc.

 

[Tealc]

I'm not familiar with these chargers but you'd expect them to only use what they need, so the answer is you probably can crank the current dial and not worry about it.

The Amps dial on bench supplies is used to limit current to the circuit under test to prevent it overloading.

 

[BUDFORCE]

I'm not familiar with these chargers but you'd expect them to only use what they need, so the answer is you probably can crank the current dial and not worry about it.

It depends, if this is something you connect directly to the battery the battery doesn't have a power circuit and you could quite easily blow up batteries doing that.

If it's to connect to a device that has its own power input/circuit, then yes provided the voltage is correct you could crank the amps to max as the device will only accept as much as it's designed to.

 

[Feek]

As the specs for the chargers just mention input voltage eg- 12-18v / 12v-32v

That's just the working input range of the charger, it doesn't mean that if you give it more volts, it'll charge faster. There will be a regulator circuit inside the charger that drops the input down to the required voltage to charge the battery. The charge voltage will be the same whether you feed it 12v, 18v or 32v.

Devices draw as much current as they need. My main shack power supply is 13.8V at 30 amps. That doesn't mean it's always outputting at 30 amps, it means it can deliver up to 30 amps if needed by the devices connected to it.

Decent supplies often have different outputs which can supply different power levels. So for example, my big shack supply has a main set of 30 amp terminals, plus others rated at five amps. I have cables that are powering devices that only need a few hundred milliamps connected to the five amp terminals.

Bench supplies are often used for testing things which is why there are terminals with different ratings. If you're working on a circuit that only draws half an amp, you'd connect it to a set of terminals with a similar rating so if anything goes bad on the circuit, you don't end up with a possible 20 amps passing through it.

 

[Magic_x_uk]

Is this to charge LIPOs?

Usually you charge at the same voltage as the battery and you can set the amps to charge, most recommend at "1c".

So a 5000mah battery you could charge at 5amps.

1000mah at 1amp etc.

Oh no, I'm fine with lipos and charging them. It was more a question regarding these bench power supplies. For the lipo chargers themselves

 

[Bear]

As Feek said, devices will draw the current that is required. The adjustable current on bench supplies is usually to set a current limit, so that if you connect and power up a circuit that has a short on it, you wont draw all the current the PSU can supply and fry your PCB.