Paralleling relay

[vdubnut62]

Any of you Gurus out there know anything about these paralleling relays? Supposedly this one is 120 volts, does that mean that it can be used
to sense  1 leg of a 240 volt system and throw a 3 pole contactor?  Or, as usual, am I  completely wrong about the whole concept?

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260504147086&ssPageName=STRK:MEWAX:IT

Ron

[mobile_bob]

as near as i can tell the unit in question senses a 120 volt line, both generator and mains

according to the truth table, the contacts will only be closed if two conditions are met

both main and generator have to be online, and both have to be sync'd then and only then will the relay close the contacts,

(that is for the second column of the truth table, known as positive logic, the first column is for negative logic)

the contacts are for pilot control of a larger relay/contactor , and they are probably rated to handle the common volts/amps for the relay/contactor
coils available.

it looks like you can dial in the voltage difference a bit too,

might be best to do a google for the unit to read up on how it works in detail

bob g

[Ronmar]

That looks to be part of a go/nogo circuit in a control panel.  Basically it helps prevent the operator from inadvertently closing a contactor untill some of the basic parameters for parallel operation are met...

[vdubnut62]

I guess I should have posted this also.
Ron

http://relays.tycoelectronics.com/datasheets/1800.pdf

[mobile_bob]

what are your plans for something like this

this model is made to allow a generator to do one of two things,

1. lock on and parallel to the mains, and presumably it could also be used to parallel two gens
but it is made to parallel connect one gen to the mains, only when the two are in phase or nearly so
(adjustable)

2. connect to the mains, when the mains are dead, which if you are connecting to the mains you probably
don't want this model in my opinion.  or it can connect to a buss that has a offline generator on it, which
means your system has no connection to the mains/utility power..

otherwise this specific unit is made to sense 120volts as i suspected, and to control an external contactor
with either 120 or 24volt coils, the 5amp resistive means it probably can handle a couple amps of a relay/contactor coil
on AC or closer to the full 5amps if you have a clamping diode on the relay/contactor coil to catch any flyback pulses.

bob g

[vdubnut62]

Use the main for a battery bank, if I can figure how to configure a motor protection relay or similar to kick everything offline
if/when main power dies.
Ron