Large DC power supply

[cgroves]

Hi all, I need to do some testing on the DF for my e-cat to determine what size batteries I am going to need for the best punch. Does anyone have access to a large DC power supply that is capable of delivering up to 80 Amps and simulating an 8 or 10s Lipo pack?

[Tom Hastie]

9S would be roughly 3 car batteries in series. How many cars do you own? ;)

That'd be one helluva power supply though. Maybe someone around does welding?

Are there any similar setups to copy on RCGroups? If you are thinking to go Thunderpower, I can give you some numbers on what my ThunderPower 3S 2100mAh prolites can put out. I don't have any recent Kokam packs though.

Tom

[miketoner]

This one almost meets your requirements.

At one of my old jobs, they had a big beefy HP6673A power supply. I picked up one time to put it on the bench and it felt like it was made out of solid cast iron. Must be the weight of all those big honking transformers in it.

From a quick google search:
The 6673A Power Supply is rated at 60 V @ 60 A and features: HP-IB Linear Output Regulation Complete Front Panel Control Calibration and Display Fan-speed control to minimize acoustic noise Low ripple and noise Over-voltage and over-current protection.

[Dave_Sawatzky]

I fear that a super heavy duty "storebought" power supply such as what MIke quoted you is probably going to run in the thousands of dollars. If you want to go "on the cheap", Tom's idea of car batteries was not a bad one. If your load is fairly constant, you can drop your voltage to the desired level by using "calibrated" pieces of wire with known resistnaces (maybe some house type wiring cut to the appropriate lengths). I have used this technique before. At 80 amps. it doesn't take much resistance to drop the voltage significantly. This technique also has the added advantage that you can measure the voltage drop across your wires and use it to calculate the current (unless you own a clamp-on ammeter, you are not likely to be able to measure 80A with a regular multimeter).

[Dynamic Man]

We have a 90 amp 13 volt bull dog supply for the slot car track.

We had to put in a 120vac 20amp service. Cost of the supply was $675.

Output voltage is not variable. other than a jumper from 13.2 to 14.1 vdc.

I think the batteries are the best way for hi current and tap into the voltage as required.

Still not very good.

Fred

[cgroves]

Yeah, it is going to be interesting because I want to get up to 25-35 Volts as well. I have access to a bunch of high amp 12V power supplies but for various reasons they can't be connected in serial. I think I'll try the car battery solution.

[Tom Hastie]

Wear rubber shoes... Don't stand in any puddles... Don't lick the exposed contacts... ummmm... Can't think of any other pointers off the top of my head.

I'll come to you if I ever need to interrogate someone.:D