Murray MP3030 duplex breaker states it's 120/240v
#1
10-09-15, 01:32 PM
Join Date: Oct 2015
Posts: 7
Upvotes: 0
Received 0 Upvotes
on
0 Posts
Murray MP3030 duplex breaker states it's 120/240v
...but I've always been told that you can't get 240v from a single bus, that you need two.
Am I missing something? Would it be possible to use a connector to attach the two breaker handles and use this to power a hot water heater?
Am I missing something? Would it be possible to use a connector to attach the two breaker handles and use this to power a hot water heater?
#2
10-09-15, 01:46 PM
but I've always been told that you can't get 240v from a single bus, that you need two.
Would it be possible to use a connector to attach the two breaker handles
#3
10-09-15, 01:46 PM
Group Moderator
Welcome to the forums.
That is correct. That breaker will only fit on one leg which means you can only get 120v from it.
I'm not sure why it's rated for 240v.
That breaker is called a tandem breaker and cannot be used for a 240v application like a water heater. You would need a two pole breaker.
That is correct. That breaker will only fit on one leg which means you can only get 120v from it.
I'm not sure why it's rated for 240v.
That breaker is called a tandem breaker and cannot be used for a 240v application like a water heater. You would need a two pole breaker.
#4
10-09-15, 01:56 PM
Join Date: Oct 2015
Posts: 7
Upvotes: 0
Received 0 Upvotes
on
0 Posts
#5
10-09-15, 02:07 PM
Group Moderator
Interesting.... it looks like that triplex breaker occupies three breaker locations. It looks to have three stabs on the back.
Actually on second look.... what looks like a center stab must be a divider slot.
Actually on second look.... what looks like a center stab must be a divider slot.
#6
10-09-15, 06:02 PM
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 16,321
Received 38 Upvotes
on
30 Posts
The MP3030 is rated for 240 volts because it COULD be used in a 240 volt, 3-phase delta panel. The MP23020 is two single pole 20 ampere circuit breakers along with a 30 ampere, 2-pole circuit breaker all in a two-pole frame. The two 30 ampere CBs have a common internal trip as well as the external handle tie.
#7
10-10-15, 07:54 AM
Join Date: Oct 2015
Posts: 7
Upvotes: 0
Received 0 Upvotes
on
0 Posts
Ah, so if the whole panel was at 240, meaning that a single bus provided 240, it would work? That makes sense.
#8
10-10-15, 11:31 AM
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 16,321
Received 38 Upvotes
on
30 Posts
The circuit breaker is rated for operation up to the rated voltage, plus a safety factor, maybe five or ten percent over the rated voltage. Use at lower voltages is always acceptable.
#9
10-10-15, 09:26 PM
The MP3030 is not rated for 240 volts. It is "slash" rated for 120/240. This means it is OK for standard single phase (120 to ground, 240 phase-to-phase) but not OK for 240 to ground.
The MP230 is their standard 2 pole common trip also rated at 120/240V AC
The MPH230 is a 2 pole common trip rated at 240V AC - specs say UL Listed for use on 3 phase grounded "B" systems
The MP230 is their standard 2 pole common trip also rated at 120/240V AC
The MPH230 is a 2 pole common trip rated at 240V AC - specs say UL Listed for use on 3 phase grounded "B" systems
