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Can you use MMP's (type F) on 3-phase industrial heaters?

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E

emiller233

Senior Member
Location
pittsburgh, pa
Occupation
Controls-Automation engineer
Can you use MMP's (type F) on 3-phase industrial heaters for hydraulic oil tanks? if not, is there a better option?
I cant find any documented info saying yes/no in regards to heaters.
Links for further reading would be greatly appreciated!

example part #
Manual Motor Protector: Eaton XTPR016DC1 (website)
Picture1.png


Type A = Fuse + motor starter where the fuse provides the SC protection for the entire motor and starter, i.e. the starter MUST have the fuse to withstand any fault current.
Type C = Thermal-magnetic circuit breaker listed under UL-489 protecting a starter listed under UL-508A.
Type D = Instantaneous trip circuit breaker (aka "MCP") listed under UL-489, with starter same as above.
Type E = Self-Protected Control Device (aka Motor Protection Circuit Breaker or "MPCB", "Motor Protective Switch" or "MPS", etc. etc.) used with a contactor, both listed together under UL-508
Type F = Manual Self-Protected Controller listed under UL-508, which is a single device that is the SCPD, controller and OL in one, no contactor.

The above info was pulled from the thread
https://forums.mikeholt.com/threads/ul-nema-cmc-type-a-c-or-d-coordination.140970/
 
petersonra

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
They are only listed for use on motors.

No reason you cannot use a circuit breaker though. If the available short circuit current is under 10kA the so called miniature CBs like ab 1489 are cost effective and work well.

There are a bunch of companies that sell them. Usually you can get them for $20-25 a pole. Up to 63 Amps.

Automation direct sells them. Forget what brand they sell.
 
J

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
PE (Retired) - Power Systems
You can use it on heater loads, only for switching/controlling . It does not provide branch circuit protection per the NEC.
 
J

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
PE (Retired) - Power Systems
petersonra said:
As far as I know all mcb sold in the US are branch circuit rated.
Click to expand...
Branch breakers need to be UL489. Not all control panel style breakers carry this listing, while all panel board style ones do. Breakers with either listing are readily available in the US.
 
petersonra

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
jim dungar said:
Branch breakers need to be UL489. Not all control panel style breakers carry this listing, while all panel board style ones do. Breakers with either listing are readily available in the US.
Click to expand...
I think all miniature circuit breakers (mcbs) sold in the US are ul489. There are similar ones rated only as supplemental breakers though.
 
Jraef

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
petersonra said:
I think all miniature circuit breakers (mcbs) sold in the US are ul489. There are similar ones rated only as supplemental breakers though.
Click to expand...
Not all. Some of the MCBs sold here (North America) only have UL1077 listing, meaning they can only be used as "supplementary" breakers, which requires that they have a UL489 listed breaker (or Branch Circuit rated fuse) ahead of them. That sort of defeats the purpose. You have to be careful in reading the specs on MCBs.

Also; most MCBs are only rated for 10kAIC or less, a FEW are 14kAIC or maybe 18kAIC, but none are rated higher than that and none have any series ratings at all, so that can get you in trouble using them, especially when it comes time to put an SCCR listing on a panel. I've seen a lot of OEMs get caught on that one, forcing the installing contractors to have to scramble for a solution, usually involving someone rebuilding the panel.

Also also; for 480V applications, all of the MCBs are "slash rated", meaning they can ONLY be used on 480/2777V 4 wire systems, they CANNOT be used on 480V delta systems (this is also true of the IEC style MMPs as well). So if you do not know for sure if the product is going to be hooked up to a 4 wire source, you shouldn't use those types of products and stick to traditional Molded Case Circuit breakers (that don't also have a slash rating).

And just to chime in on what was already said, MMPs can only be used on MOTOR circuits. Siemens does have an MMP style device that is UL489 listed as a branch circuit breaker, but to attain that, it has fixed trips. It is actually MORE expensive than an MCCB of the same rating and carries the 4 wire system restriction, so I have no idea why anyone would use one, but it's out there... I think maybe they do it for people who will be using through-the-door handles and have other MMPs in the panel, so all the handles would look the same, I guess.
 
Last edited:
E

emiller233

Senior Member
Location
pittsburgh, pa
Occupation
Controls-Automation engineer
Jraef said:
Not all. Some of the MCBs sold here (North America) only have UL1077 listing, meaning they can only be used as "supplementary" breakers, which requires that they have a UL489 listed breaker (or Branch Circuit rated fuse) ahead of them. That sort of defeats the purpose. You have to be careful in reading the specs on MCBs.

Also; most MCBs are only rated for 10kAIC or less, a FEW are 14kAIC or maybe 18kAIC, but none are rated higher than that and none have any series ratings at all, so that can get you in trouble using them, especially when it comes time to put an SCCR listing on a panel. I've seen a lot of OEMs get caught on that one, forcing the installing contractors to have to scramble for a solution, usually involving someone rebuilding the panel.

Also also; for 480V applications, all of the MCBs are "slash rated", meaning they can ONLY be used on 480/2777V 4 wire systems, they CANNOT be used on 480V delta systems (this is also true of the IEC style MMPs as well). So if you do not know for sure if the product is going to be hooked up to a 4 wire source, you shouldn't use those types of products and stick to traditional Molded Case Circuit breakers (that don't also have a slash rating).

And just to chime in on what was already said, MMPs can only be used on MOTOR circuits. Siemens does have an MMP style device that is UL489 listed as a branch circuit breaker, but to attain that, it has fixed trips. It is actually MORE expensive than an MCCB of the same rating and carries the 4 wire system restriction, so I have no idea why anyone would use one, but it's out there... I think maybe they do it for people who will be using through-the-door handles and have other MMPs in the panel, so all the handles would look the same, I guess.
Click to expand...
i think this Siemens version is what i was thinking of, bc I remember them using a busbar to feed the entire din rail of Cb's and MMPs
 
Jraef

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
petersonra said:
I did not think supplementary breakers are referred to as miniature circuit breakers, even the ones that are the same form factor.
Click to expand...

24449 - Multi9 - C60 UL1077 - MCB - 2P - 10 A - C Curve - 480Y/277 V - 5 kA | Schneider Electric USA

Schneider Electric USA. 24449 - Multi9 - C60 UL1077 - MCB - 2P - 10 A - C Curve - 480Y/277 V - 5 kA.
www.se.com www.se.com

 
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