Breaker Sizing for 200V motor

[taylorjtt]

I am trying to size a breaker for a 3-phase 200V air-compressor motor inside of a commercial device. The nameplate of the motor reads as follows

3.0HP
200V
9.2FLA
SF 1.15
FR 56CZ
INS B
ENC Open
PH 3
THERM TYPE N
KVA CODE J
MAX AMB 40 Deg C

We are currently using a 13,13,10 breaker for the entire system , however we are experiencing widespread nuisance tripping.

The question we are trying to get to the bottom of is are we able to go up to a 15A breaker on this system. From the research I have done I have found out that for OVERLOAD protection, the cutoff is 125% FLA which is only 11.5A. The motor has built in thermal protection, but I haven't been able to find much information on thermal type N protection, so I do not know if it qualifies as adequate overload protection. From the information I found on Short-Circuit protection, the lowest rated standard breaker is 15A.

Any suggestions are appreciated. I'm a microcontroller guy so these standards are foreign to me.

 

[augie47]

If the breaker serves as Shot-Circuit-Ground-Fault Protection, 430.52 would allow the breaker to be a 30 amp.
That said, I can not verify they Type N thermal is adequate OL protection.

 

[kwired]

I am trying to size a breaker for a 3-phase 200V air-compressor motor inside of a commercial device. The nameplate of the motor reads as follows

3.0HP
200V
9.2FLA
SF 1.15
FR 56CZ
INS B
ENC Open
PH 3
THERM TYPE N
KVA CODE J
MAX AMB 40 Deg C

We are currently using a 13,13,10 breaker for the entire system , however we are experiencing widespread nuisance tripping.

The question we are trying to get to the bottom of is are we able to go up to a 15A breaker on this system. From the research I have done I have found out that for OVERLOAD protection, the cutoff is 125% FLA which is only 11.5A. The motor has built in thermal protection, but I haven't been able to find much information on thermal type N protection, so I do not know if it qualifies as adequate overload protection. From the information I found on Short-Circuit protection, the lowest rated standard breaker is 15A.

Any suggestions are appreciated. I'm a microcontroller guy so these standards are foreign to me.

If motor already has thermal overload protection that leaves you with short circuit and ground fault protection from your breaker. As mentioned for an inverse time breaker this motor can be on a 30 amp breaker, FLA from T430.250 x 2.5. If that won't let it start it can be increased up to 4x FLA, this from 430.52.