PL8 current draw

[MaxWatts]

Hi,

I've just joined here, as I've been googling for an answer to a problem I'm having.

I bought a Powerlab 8 recently, and have an old Maplin 30V - 2.5A power supply for charging indoors until I figure out a decent power supply to purchase.

I'm probably doing something wrong, but I've read the manual, and searched the 'net for an answer, before wasting anybody's time with stupid questions.

I connected a Turnigy 5000mah 4s to the PL8, with the balance connector only, and went with the factory preset number 1, Accurate Charge. I changed the charge current to 2.0A, bearing in mind the power supply. From what I've read, the balance connector is good for rates up to 3A.

After the PL8 starts, the VU meter on the PSU slowly rises to show 2 amps, then goes back to 500 milliamps, and stays there. It does exactly the same for presets two and three. No matter what I input as a charge rate, it rises, then settles back to 500ma...

Is it me? I'm a beginner in this field, and think I've probably missed something. The PSU is set for max voltage [30v] and max current [2.5A] and is quite capable of supplying it.

What am I doing wrong? Any suggestions would be much appreciated!

Regards,


Max

[Tim Marks]

Originally Posted by MaxWatts

Hi,

I've just joined here, as I've been googling for an answer to a problem I'm having.

I bought a Powerlab 8 recently, and have an old Maplin 30V - 2.5A power supply for charging indoors until I figure out a decent power supply to purchase.

I'm probably doing something wrong, but I've read the manual, and searched the 'net for an answer, before wasting anybody's time with stupid questions.

I connected a Turnigy 5000mah 4s to the PL8, with the balance connector only, and went with the factory preset number 1, Accurate Charge. I changed the charge current to 2.0A, bearing in mind the power supply. From what I've read, the balance connector is good for rates up to 3A.

After the PL8 starts, the VU meter on the PSU slowly rises to show 2 amps, then goes back to 500 milliamps, and stays there. It does exactly the same for presets two and three. No matter what I input as a charge rate, it rises, then settles back to 500ma...

Is it me? I'm a beginner in this field, and think I've probably missed something. The PSU is set for max voltage [30v] and max current [2.5A] and is quite capable of supplying it.

What am I doing wrong? Any suggestions would be much appreciated!

Regards,


Max

Hi:

Obviously that PSU is terribly inadequate for the PL8, but I guess you already realize that. Did you follow the guidelines in the user guide and set the input current limit on the PL8? If not, then the first thing you need to do is set that input supply limit to something like 2A. This will protect your weak PSU and prevent the PL8 from ever drawing over the limit you set; regardless of where you set the charge rate. Also, set the input low voltage down to something like 27V if you're inputting 30V.

Then give it another go and see if it works better for you.

Here's the link to the user guide:

http://www.revolectrix.com/pl8_links_tab.htm

First link on the Resources tab.

Start reading on page 9.

If you still get stuck at 500 mA, the PL8 may be going into safety charge which limits to 500 mA. This could be an indication of a problem with your battery. Let me know how you make out.

Tim Marks

[kyleservicetech]

Originally Posted by MaxWatts

Hi,

I've just joined here, as I've been googling for an answer to a problem I'm having.

I bought a Powerlab 8 recently, and have an old Maplin 30V - 2.5A power supply for charging indoors until I figure out a decent power supply to purchase.

I'm probably doing something wrong, but I've read the manual, and searched the 'net for an answer, before wasting anybody's time with stupid questions.

I connected a Turnigy 5000mah 4s to the PL8, with the balance connector only, and went with the factory preset number 1, Accurate Charge. I changed the charge current to 2.0A, bearing in mind the power supply. From what I've read, the balance connector is good for rates up to 3A.

After the PL8 starts, the VU meter on the PSU slowly rises to show 2 amps, then goes back to 500 milliamps, and stays there. It does exactly the same for presets two and three. No matter what I input as a charge rate, it rises, then settles back to 500ma...

Is it me? I'm a beginner in this field, and think I've probably missed something. The PSU is set for max voltage [30v] and max current [2.5A] and is quite capable of supplying it.

What am I doing wrong? Any suggestions would be much appreciated!

Regards,


Max

Yeah
As Mr. Marks points out, your power supply is woefully inadequate to run your PL8 charger. I've got mine charging a 6S4P A123 battery pack at 30 Amps. It's pulling over 50 amps out of a 12 Volt DC supply.
(Here is one way to build a field charger capable of 80 Amps at 13 Volts DC. Harbor Freight Gasoline/Alternator Setup
http://www.wattflyer.com/forums/showthread.php?t=66066,)

A number of different power supplies are available, some brand new, some used. Several club members have purchased these used computer server power supplies, and have had good luck with them.
http://www.feathermerchantrc.com/

[MaxWatts]

Hi guys,

Thank you for the replies!

Tim, I have read the manual, and set the supply limit [to 2A] accordingly. Yup, I realise that this power supply is totally inadequate - it was one I had from ages ago, and figured it will do until I choose a proper one.

Your comment about the battery is noted. I have some more arriving this week, and can't wait to compare.

Dennis, thank you for your reply, and your links. That generator looks way cool[!], as do the server power supplies. I never realised how many choices there were in this field! I'm off to do some more reading.

Thanks again, guys - I appreciate you taking time out to help a noob...

Max

[kyleservicetech]

Originally Posted by MaxWatts

Hi guys,

Thank you for the replies!

Tim, I have read the manual, and set the supply limit [to 2A] accordingly. Yup, I realise that this power supply is totally inadequate - it was one I had from ages ago, and figured it will do until I choose a proper one.

Your comment about the battery is noted. I have some more arriving this week, and can't wait to compare.

Dennis, thank you for your reply, and your links. That generator looks way cool[!], as do the server power supplies. I never realised how many choices there were in this field! I'm off to do some more reading.

Thanks again, guys - I appreciate you taking time out to help a noob...

Max

Or, if you want to buy brand new with a two year warranty, check out this Jameco unit. Jameco has been around for decades and will sell to anyone with a credit card. These units are designed to operate 24 hours a day, 365 days a year.

The Jameco Meanwell power supply has simple terminal screw connections. (The AC input requires three wires, hot, neutral, mechanical ground, and, isolated 12 Volts DC output, with three screw connections for 12 Volt negative, and three more screw connections for 12 Volt positive.) Meanwell is a major supplier of these type power supplies.

If you have any small children around, you'll need to cover the 120 VAC terminals with some short of non-metalic shield.

http://www.jameco.com/webapp/wcs/sto...001_2094928_-1



???
3 AM? you stay up later than I do!

[MaxWatts]

Originally Posted by kyleservicetech

Or, if you want to buy brand new with a two year warranty, check out this Jameco unit. Jameco has been around for decades and will sell to anyone with a credit card. These units are designed to operate 24 hours a day, 365 days a year.

The Jameco Meanwell power supply has simple terminal screw connections. (The AC input requires three wires, hot, neutral, mechanical ground, and, isolated 12 Volts DC output, with three screw connections for 12 Volt negative, and three more screw connections for 12 Volt positive.) Meanwell is a major supplier of these type power supplies.

If you have any small children around, you'll need to cover the 120 VAC terminals with some short of non-metalic shield.

http://www.jameco.com/webapp/wcs/sto...001_2094928_-1

Excellent! Thanks again for the tip, Dennis! This Jameco PSU looks like great value for money...

???
3 AM? you stay up later than I do!

Haha! Never occurred to me that anybody would pick up on the time! My body clock is all over the place! Curse this internet invention thing...


Many thanks,


Max