HP HSTNS-PL11 psu Over Voltage Protection voltage increase?

[deadlistcach]

Hello I read most of comments videos etc.

I have some questions.

I have 2 PL11 rev10 psu. I did OVP and 14.4v mod already. they work seperately very good.


I wanted to use them in series configuration. because of this I floated one of them. and made 24v. I mean 28.8v.

as series right now its working without any load.


I noticed something when I test in home one of (non isolated + goes to isolated psu -) isolated psu get more hot then not isolated. I mean not very hot, one of them like ıce other little warm. I watchend BBI on youtube he do serious parallel configurations. and I know these psu's have load sharing.

Can I do series connection and load sharing in same time?    or I needed to do this?

thank you who read and give answer.

[eblc1388]

Load sharing only applies to power supplies connected in parallel. e.g. two 40A power supplies providing 60A to a load. You don't want the situation of 40A+20A from the supplies so you connect them up with load sharing. This will equalize the loading and each power supply will then provide 30A.

In case of series power supply connection in your case, there is only one load current value for both supplies, and this is the same for the two power supplies.

You don't need any current sharing. In fact the only thing you can do is output power adjustment by changing the output voltage on one of the supplies.

[deadlistcach]

Thank you for fast reply.

if I dont need load share its good.(I just saw on internet and wonder) Today I test 30A load at 5 min everthing ok right now.

when I do voltage increase with resistor, one of supply 14.3 other became 14.35-38v with 5k resistor.

I check 2 small potentiometer before do anything one psu 53-24 second 48-56 there was different. So I open 2 of them and set 14.40v at idle.

Do I need to do someting about starting psu's. just put switch ac power?

[eblc1388]

Do I need to do someting about starting psu's. just put switch ac power?

Most people just switch On/Off the mains ac power to these supplies via a single switch, and they work fine. Most will find no problem in doing so.

However, the proper way to do it would be to add reversed-polarity diodes at output of the supplies to deal with the difference in timing regarding powering up/shutdown of each supply. Please read the following thread about how to wire it up.

https://www.eevblog.com/forum/beginners/can-this-power-distribution-board-will-handle-1200w/

[deadlistcach]

Hello,

As you said I added reclifier, its 35a I will add one more paralel if I need(my load will be max 45A), but i dont understand how it works because we do bridge from 12+ to other psu negativeto 24v electric can stil go. Anyway I read most of your comments you know these issue



I willchange cables if everything ok tomorrow load test.

[eblc1388]

The added 35A rectifier(goods for up to 70A loading) is more than sufficient for the protection purpose, and you definitely does not need to add more in parallel.

The added diodes(bridge rectifier) is a form of protection to prevent the components inside each power supply from reversed polarity voltage, when one power supply starts up faster than the remaining one. This condition exists for a brief moment during power up, through the connected load, a reversed voltage will be present across the output of the remaining one. It may or may not damage the component immediately in the short term, but there is a risk it could after more power up sequences. As a form of protections, user will not notice any difference without these diodes being connected. 

[deadlistcach]

Thank you for explanation, today I could do test. (half hour)  I was trying to run PWM Solar Charger as dc dc charger, with 2 PL11 power supply works good.

my batteries was not full but they had 26v. I also open some lights I wast 15A max on test. Thank you for helping


do you have knowledge about pwm chargers? I also have some questions.

[eblc1388]

Glad it all work out ok.

You can start a new thread on problems with PWM Solar Chargers and I'm sure many members here can offer their help.

[AirShox]

Greetings,
I have PL11 with version 14 and 16. Unfortunately they do not have the same components and I cannot overcome the OVP. I can only power them ON to test if they are not dead on arrival.
Does someone have used version greater than 13 (I have one and it works flawlessly) with success?

[pienari]

We need pictures.

[AirShox]

Thank you in advance!
PL11 ver16

[AirShox]

Sticker as well

[sp3rat]

Hello Pablo.
I have the same problem with my fan.
Without load, it works quickly and noisily, and with load, it works slowly and very quietly.
Have you already solved this problem?
Greetings to everyone.
Jurek sp3rat