Blown PDUs?

[BillP]

We recently purchased some PDUs (AP7811s) from a vendor which listed them as "refurbished". Upon installation, it became apparent that hte units were not fuctioning properly. Input power brought the unit up, but power was not be distributed out the output ports. Management showed all systems nominal. Furher investigation revealed that the "fuse" switches (I don't know the proper term) did not engage properly. What I mean is, on a functioning unit. using a flat-head screwdriver to push on the switch flips it with a solid thunk and the power cuts out. Pushing the "on" side of the switch gives you resistance and the switch engages again with a click and the power resumes to the bank. On these units, that does not happen. The switches do not cutout but pushing the off button merely changes the state of the plastic switch, without resistance and no click. Same with turning the switch back "on" again, although at no point is any power getting to the bank.

Is this a case of a blown part? Is this end-user repairable? I am reticent to bother with these units and prefer to just return them and get my money back but I just want to confirm that this would seem proper. Reviewing the manuals shows me nothing about these switch states and what has happened if they can be engaged without action.

We have other identical units that act as I would expect.

Comments? Am I missing something?

[Anonymous user]

You sound like you are familiar with the proper procedure for resetting the circuit breakers which can be difficult in itself. From the description provided and the fact you have other units of the same model behaving differently, I would think your best option would be to return these to the purchaser. Did you purchase these direct from APC or a company that sells refurbed units?

[BillP]

We purchased them from a reseller who advertised them as refurbished. Certainly all normal "buyer beware" notices apply in such a situation although the seller affirmed the units were functioning properly. They have a money back guarrantee so I assume I'll be ok.

[BillP]

Mmmmm, just to make sure that we are talking about the same thing - when you talk about resetting the circuit breakers, are you talking about replacing parts inside the unit? I assume not and that you're just talking about resetting the external switches. Because I've not opened the things up and looked inside. Unless there is a way to do that without voiding the warranty, I will just return them.

[Anonymous user]

Hello,

The circuit breakers would be on the outside near the input power cord. Do not open up the PDU, as like you said, it will void warranties.

[Anonymous user · Accepted solution]

These rPDU's have what is called a mid-trip breaker. You need to push the breaker into the full off position before you can push it to the full on position. If the breaker is tripped due to an overload it should go to the mid-trip position, and will need to be reset before being usable again.

Use a small screw driver and push through the breaker slot until the breaker engages the off position. Then push it to the on position.