To be fair modern panels are pretty good at monitoring batteries. In this case the low voltage appears to be due to the battery going flat.

I'd agree that an intelligent power supply would of shown this early on but not everyone used en as using a normal psu was cheaper. Only short term mind if you factor this fault alone it would of been a lot cheaper to use intelligent power supplies Lol.

i don't think this job was G3 afiik monitored PSU's are mandatory now to meet G3.

i'm not sure of this, but i think even to be a G2 the main panel has to monitor (and warn of) mains power failure, if that is so should not the psu's also do this?

would make good sense, the expander could have a simple link, which selects if locally powered or remote psu, all it then needs is to monitor the ac from the tranny and the aux volts in from the PSU

Arfur

If it's g2 then yes, id assume it's a 4737

Job. But it may be an un certified job and may not need anything

As others have said always monitor your exp psu's, Use the Aux input programmed as mains failed.

better to prog as psu monitor, you get all the faults that way, using a few resistors.

To be fair modern panels are pretty good at monitoring batteries. In this case the low voltage appears to be due to the battery going flat.

I'd agree that an intelligent power supply would of shown this early on but not everyone used en as using a normal psu was cheaper. Only short term mind if you factor this fault alone it would of been a lot cheaper to use intelligent power supplies Lol.

As above, any cheap PSU with a few outputs can be monitored easy enough with prems.

better to prog as psu monitor, you get all the faults that way, using a few resistors.

True but resistors are used on premier 48's and up, prem 24 is nc /no only on the aux input, it also depends on the psu being used not all

come with relays built in... If not a single very handy little relay does the trick to monitor mains power failure.

Edited December 22, 201015 yr by Couger

True but resistors are used on premier 48's and up, prem 24 is nc /no only on the aux input, it also depends on the psu being used not all

come with relays built in... If not a single very handy little relay does the trick to monitor mains power failure.

on a basic psu with LED power indicator, you could use a transistoried relay, feeding the input from the LED, or using a simple diode as a 1/2 wave rectifier and a small smoothing cap, wire the coil from the ac input to the PSU,

above is ideal if you get the problems that simply don't make normal sense, you can at least illiminate the PSU from the equasion

where i've needed, i like the Risco G3 PSU's, loads of space for expanders having two relays on board as well as battery protection, makes it easy to wire as zones and program as needed.

Arfur