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WS-12-250-DC shuts inadvertently down

Posted: Wed Aug 03, 2016 4:13 am
by rste
Yesterday we installed two new WC-12-250-DC to our system.
These Switches are mainly powered by a power supply, but to prevent power failures we have also added a battery block.

Normally when the power supply is running, the switch is powered with 58V input. If something happens which causes a power failure the switches are powered by the battery block. The Battery Block provides 51 V when they are full. The emptier the battery block the lower the voltage.

Normally the switch should fit with 9 to 60V, but in our case the switch just shuts down when the input voltage is below 48V.

Image

We monitored the input voltage, in this picture you can see how it looks like in prtg.
At 3pm the power supply does not work eg. caused by a power cut. The Battery provides ca. 51V.
At 4.30 the switch turns off, and the last voltage it gets is 47.83V
As you can see, the voltage drops faster at ca. 4.20pm, maybe switch can not fit with a bit faster voltage drop?

Re: WS-12-250-DC shuts inadvertently down

Posted: Wed Aug 03, 2016 7:48 am
by sirhc
This is not possible.

1) What is the power supply your using?

2) Is the switch connected "directly" to the batteries or does it connect to what ever power supply your using?

3) Post pictures of the Status, Power, and Device/Status Tabs

Re: WS-12-250-DC shuts inadvertently down

Posted: Thu Aug 04, 2016 5:24 am
by rste
Thanks for your fast response. :hurray:

1)We are using a Lithium Battery Charger, i dont have a exact product identification. It provides 58.4V and max 10A.

2) The Batteries and the Charger are directly connected to the switch
Image

3) And the screenshots

Image

Image

Image

The Switch normally needs 200 to 210 Watts.(displayed in the dashboard)

One thing is I have noticed:
On the device status page you can see that the switch currently needs ca. 3.8A from max 4A. Is 4A really the max value? If yes, could it be that switch just needs to many amperes?
Example:
Input Voltage 58.4V
Input Ampere 3.8A
-> Needed power: 221.92 W (minus the psu efficiency of the switch it fits with the value which is displayed in the dashboard)
If the switch is powered by the batteries and only gets eg 47.5V:
Input Voltage 47.5V
power: 221.92 W
Needed ampere: 4.6A
I didn`t find any information about how many ampere the switch can withstand. Could this be problem?
I don`t have a very big knowledge in physics and energy, but my head tells me this could be a problem. :crazy:

Re: WS-12-250-DC shuts inadvertently down

Posted: Thu Aug 04, 2016 9:01 am
by sirhc
Please update the picture of the Power Tab, I need the top input values on the power tab you cut off such as hibernate

Also on at least one picture show the top portion of the screen with the switch graphics

By the way you can upload pictures to the forum, look for the link "Upload attachment" next to the BLUE Preview and Submit buttons

Re: WS-12-250-DC shuts inadvertently down

Posted: Thu Aug 04, 2016 9:30 am
by rste
Oh, so i attached the updated image of the power tab.

Re: WS-12-250-DC shuts inadvertently down

Posted: Thu Aug 04, 2016 11:17 am
by sirhc
Do you know that the whole switch shut down or possibly it just shut down port 1 as it had the lowest priority?

Can you confirm the whole switch shuts down, you can confirm this by looking at up time on the switch and the AF radios

Re: WS-12-250-DC shuts inadvertently down

Posted: Thu Aug 04, 2016 4:33 pm
by sirhc
I am thinking your Lithium batteries are not adequate to handle the load which is evident in the speed in which they discharge.

The AC power goes out and the Lithium's voltage drops FAST.

Lithium batteries that discharge fast heat up fast and then they start eating themselves meaning they drop faster.

Why are you using Lithium batteries to begin with?

I would use AGM Batteries (I like Optima Blue Top) and a 4 stage charger (I like Minnkota) that can recover a battery that is fully discharged. You need 10A per battery to recover a fully dead battery.

Re: WS-12-250-DC shuts inadvertently down

Posted: Thu Aug 04, 2016 4:56 pm
by Texwire
Easy test is to hook up the 4 AF's directly to fully the fully charged batteries. Disconnect charger and see what it does. Can this be done for a bit where you are at?
Kevin

Re: WS-12-250-DC shuts inadvertently down

Posted: Fri Aug 05, 2016 6:08 am
by rste
So, yes the complete switch shuts down and so also the AF´s. Because they are powered by the switch.

Re: WS-12-250-DC shuts inadvertently down

Posted: Fri Aug 05, 2016 8:21 am
by sirhc
sirhc wrote:I am thinking your Lithium batteries are not adequate to handle the load which is evident in the speed in which they discharge.

The AC power goes out and the Lithium's voltage drops FAST.

Lithium batteries that discharge fast heat up fast and then they start eating themselves meaning they drop faster.

Why are you using Lithium batteries to begin with?

I would use AGM Batteries (I like Optima Blue Top) and a 4 stage charger (I like Minnkota) that can recover a battery that is fully discharged. You need 10A per battery to recover a fully dead battery.