What might cause a switch to STOP.?

[tomtech]

Let me explain
We have a new (2 month since we purchased) WS3 switch. Its been in production at a tower for about 5 weeks. Its a DC switch serving only 24v to POE AP's mostly Ubiquiti and Cambium. DC is supplied from a ICT modular serving 56v. It has been working perfectly, then one saturday at 3am, it stopped. When I got on site the power light was off, fans off, no LED's anywhere. Voltage perfect at the terminals. Power cycle got a green power light and fans, but it shut down after about 90 seconds. No ammoiunt of power cycle, waiting for 30 min, then power up, changing DC circuits, nothing got the switch running. We swapped it for a Mikrotik because we need to service our customers. Brought it back to the shop and before we RMA'd it I decided to pwoer it up, and it came up. I reset it to factory and its working fine. I left it on for a day and it still works. But I am NOT putting it in production until I understand why this would happen.

So, thats the question, what would cause a switch like this to bork so badly, then come back to life???

I appreciate your attention to this matter.......

Tom

[sirhc]

No idea.

Please explain how your powering it again?

Is this a site with AC or off grid?

If off grid with battery bank it must be connected directly to the the batter bank not a controller.

Read these posts and links and links on those posts.
viewtopic.php?f=6&t=4450&p=27007&hilit=+heaven+forbid#p27007
viewtopic.php?f=6&t=5986&p=31662&hilit=directly+to+battery+bank#p31662

hooking to charging controllers can cause issues and intermittent power flickers can corrupt flash which makes sense that a power on factory default corrected.

[tomtech]

Site Is NOT off grid. ICT manufacturers broadband focused power products for grid tied and off grid applications. Our DC controller manages charging of a bank of 4 190AH lead acid batteries and connects to a DC power distribution module that feeds various devices on the tower. We do all our 48/56v from this device using a 9dot POE injector, and all our 24v mid span through the Netonix.
This is the link to our power controller: https://ict-power.com/product/hybrid-power-series/
This is the link to the DC power distribution module: https://ict-power.com/product/ict200db-12irc/
All DC buss outputs are protected by circuit breakers. We follow all grounding rules. The Power modules have no alerts or errors and our SNMP monitoring shows no unusual events from any gear except loss of signal.
Hope this helps provide some context.

[Dawizman]

I had a Netonix do something very similar with an ICT power supply. Are you using ICT controllable circuits? As in the breakers on that PDU?

[tomtech]

Ya, we have an ICT modular doing battery charging, and a DC buss controller with breakers connected to the main DC battery buss. Technically, the DC power comes straight from the battery. We opened a ticket with ICT and they are looking into it to be sure there was no funny business with the power, but we have had Netonix do the same thing with AC power. We have almost 300 subs on this tower and cant afford having outages like this, so were checking with everyone.

[Dawizman]

Ya, we have an ICT modular doing battery charging, and a DC buss controller with breakers connected to the main DC battery buss. Technically, the DC power comes straight from the battery. We opened a ticket with ICT and they are looking into it to be sure there was no funny business with the power, but we have had Netonix do the same thing with AC power. We have almost 300 subs on this tower and cant afford having outages like this, so were checking with everyone.

So this is what I have seen with the Intelligent ICT PDUs. They are always outputting voltage in order to test if the circuit breaker is on or off. I cant recall the exact situation now, as this was about a year ago now, but we had a couple of these cases where a netonix just stopped working, powered through an ICT PDU.

My theory is that if you turn the output OFF via the network control, the switch still gets some voltage. Enough to power up the netonix power supply, but not enough to boot the switch. This puts the switch some sort of failure condition (Maybe Chris can speak on this further - powering the switch without enough amps for the initial boot), and then even when you turn the output "ON" on the ICT, it still wont boot.

When you were power cycling, were you flipping the breakers, or using the network control of the ICT to disable & re-enable?

I believe what we had to do was turn the breaker OFF for about 30 seconds, and then back on for the switch to boot. I haven't thoroughly tested, but setting "Ignore Circuit Breaker Status:" on the output n your ICT may resolve this issue.