Originally Posted by Robo1981

hi, on the KD175 PowerSupply at 14,4V with disabled OVP, the integrated OCP triggers faster than an external 100A fuse ?



still a question: which of these 2 powersupplys is better to mod up to 14,4V with very high output power?

http://www.ebay.de/itm/150890165971?...84.m1438.l2649

or http://www.ebay.de/itm/DELL-POWER-SU...-/110949829545

"A standard fuse may require twice its rated current to open in one second,
a fast-blow fuse may require twice its rated current to blow in 0.1 seconds,
and a slow-blow fuse may require twice its rated current for tens of seconds to blow."

The KD175 will trip exactly at OCP (130A-140A) but the 100A fuse will handle more peak current for a short period of time.
Therefore, the KD175 OCP will trigger before the 100A fuse blows in your particular situation(powering a car amplifier).

The DPS-20000BB is better to mod up to 14.4V with very high output power.

Voltage is adjustable up to 14.6v with revisions S8M and lower.

Internal pot VR601 = OCP adjust. 196A @12V max at low setting to 215A@12V max at high setting.

You will need to add cooling fans.

http://www.rcgroups.com/forums/showp...&postcount=611

http://www.rcgroups.com/forums/showp...&postcount=997

The Dell AHF-2DC 2100W PSU does 175A at 12V and OVP is set at 14.1V.

Originally Posted by xandrios

"A standard fuse may require twice its rated current to open in one second,
a fast-blow fuse may require twice its rated current to blow in 0.1 seconds,
and a slow-blow fuse may require twice its rated current for tens of seconds to blow."

Fuses only work to save wires from turning into fire-starters. They are (as stated) too slow to save either the PSU or anything connected to it.

I just posted a build thread for a complete conversion of a Dell 7000814 power supply. It's at http://www.rcgroups.com/forums/showthread.php?t=1750411. There's not much new here except sources for parts and a few tips, but it does pull together into one place a lot of information scattered all over several threads in this forum. These power supplies are cheap on eBay and elsewhere. If you need a power supply, take a look at this thread.

Been trying to figure out why I have 6V AC across the cases of my 2 DL580 870W PSUs in series.
I noticed the unmodified PSU has continuity between AC ground and both +5V prongs.
Is this normal?

Thanks, Danny

P.S.: I'm expecting my new Fluke 175 DVM this week, will be more accurate than my cheapo Voltcraft.

Originally Posted by Remklep

Been trying to figure out why I have 6V AC across the cases of my 2 DL580 870W PSUs in series.
I noticed the unmodified PSU has continuity between AC ground and both +5V prongs.
Is this normal?.

I assume 5V ground is also connected to case/AC ground on the unmodified ones? In that case, it would mean that the 5V is shorted, which I assume it is not.
Have you tried to "load" the 6V you are seeing with a resistor?

Fred

Well, ist seems my problems with my 2 DL580 870W PSUs have been solved.

First of all I must correct a statement I made earlier, there is continuity between the ground (AC and DC) and +3.3 V prongs on the unmodified PSU.
I have no idea if this is normal, but is seems to work.

Today I received my new used Fluke 175 DVM which I bought from eBay.
When I measured the Voltage across the cases it read as 0.00 V at 0 Hz.
So I guess my cheapo Voltcraft DT-21 really is not that good.

I'm happy.
Next week I'm getting 2 more DL580 870 W PSUs and 2 DL580 1300W PSUs.

Danny

can two power supplies connect parallel with 14,4volt and max 400amps ?

2 *dps 2000bb

Yup. But you might max out a 220v 20a outlet..

Delta DPS-1001AB-1 48V 700w/1000w, Delta DPS-1500AB A Full Pinout.

700w output with 110V-120V input. 1100w or 1500w output with 220V - 240V input depending on model,

Connect PS on and PS Kill to ground to power up.

Cisco 6500 series Sony APS-162 42V 27.5A 1300W Power Supply 100V-240v. No modification needed.

Just plug into an outlet and turn the switch to the on position and It will power up.

Also good for parts because they are inexpensive. Has a large 12V fan and a very nice power switch.

I bought one of these 100A meters for mounting permanently on the 12V 100 supply.

Delivery speed and price at $13 delivered were great but it is hopelessly inaccurate and unlike the Volt/Amp/Capacity/Power meter that xandrios and I got earlier cannot be calibrated.

At 46.4 Amps it read 70.4A. Over 50% error!

Suspect it is a poor AD convertor in the display as the actual voltage across the shunt was 37.9mV. Given it is a 75mV/100A shunt that's reasonably close.

That is it should display 100 * 37.9/75.0 = 50.5A which is about 9% error. Not good but would be acceptable since it would be fairly simple to trim the shunt with an extra wire.

Don't waste your money.

http://www.aliexpress.com/snapshot/201906796.html

John

Yup. Those Volt/Amp/Capacity/Power meters are very accurate. Plus they update the info much faster.

Hey jj604, Are you sure there isn't a trim pot on the back of the meter? Most that I've come across have one.

These particular DC panel meters seem to be very susceptible to EMI.

The closer I moved the shunt sense wires to the PSU, the more inaccurate the meter became.

A 100k resistor in series with one of the meters shunt wires (resistor has to be close to the meter) should help with accuracy.

I had a similar problem with accuracy and the resistor helped tremendously.

Originally Posted by xandrios

Delta DPS-1001AB-1 48V 700w/1000w, Delta DPS-1500AB A Full Pinout.

Thanks. Are one of those pins used for current share? I was thinking about running two in parallel and was under the impression that connecting the current share pin is a recommended practice.

You're right thanks - there is. Smallest trim pot I have ever seen. I thought it was just a blob of solder!

I will try calibrating it and then see how linear it is.

Not much help for the average Joe who buys this thing expecting it to accurately measure current though.

I may have just got a "it's late and I'm a tired worker" one. I sometimes wonder if any of these gadgets are actually calibrated or whether they just assemble them with the settings the pots come out of the box with.

John

Originally Posted by xandrios

Yup. Those Volt/Amp/Capacity/Power meters are very accurate. Plus they update the info much faster.

Hey jj604, Are you sure there isn't a trim pot on the back of the meter? Most that I've come across have one.

John,

Thanks for creating this Thread and "How To", I bought the PS off of Fleabay, and it was an easy setup.. this PS easily powers my Hitec X2 charger... The hardest part I had with the conversion was that the Power connection on the PS that I received didn't have a standard connection that I could have used a standard computer Power cord, so I had to make one myself.. Not all that difficult tho..

Thanks again.

Craig.