11-04-2012, 04:46 PM
Comparison between MPR300 and Bimetal relays
[attachment=19941]
Traditional Method to protect the Motor
Normal connection
1.Fuse.
2.Thermal Bimetallic Relay .
3.Contactor.
4.Motor.
Type of Protection offered by the scheme
1.Short Ckt.
2.Over Load
Type of protection offered by Relay
1.Thermal Overload.
2.Lock- rotor.
3.Earth fault.
4.Single Phasing .
5.Phase Sequence Preventer.
6.Load Unbalance.
7.Under Current.
Bimetallic Relay
Qu.Can you get the cause of tripping with B.M.R.?
Qu.Are you getting Earth fault protection /Phase reversal preventer/unbalance load /Under current thru B.M.R.?
Qu.Is it economical to put no. of relays for no. of protection in comparison to put only one relay & get all the protection?
Qu.Do you know that B.M.R.can give nuisance tripping in hot weather,& interrupt your production & in the cold season it will take longer time to trip?
Qu.Do you know after tripping and rectification of fault you can not run the motor until & unless the bimetal strip cools down (wasting of precious production time)?
Qu.Whatever protection you are getting thru the B.M.R., are they adequate to protect the motor?
Dual saving of Money
1.Since u will get the cause of tripping as soon as fault occurrence.
2. You can save the time to locate the
fault.
3.The chances of damages due to faults other than over load is eliminated.
4. Production loss will be very low.
[attachment=19941]
Traditional Method to protect the Motor
Normal connection
1.Fuse.
2.Thermal Bimetallic Relay .
3.Contactor.
4.Motor.
Type of Protection offered by the scheme
1.Short Ckt.
2.Over Load
Type of protection offered by Relay
1.Thermal Overload.
2.Lock- rotor.
3.Earth fault.
4.Single Phasing .
5.Phase Sequence Preventer.
6.Load Unbalance.
7.Under Current.
Bimetallic Relay
Qu.Can you get the cause of tripping with B.M.R.?
Qu.Are you getting Earth fault protection /Phase reversal preventer/unbalance load /Under current thru B.M.R.?
Qu.Is it economical to put no. of relays for no. of protection in comparison to put only one relay & get all the protection?
Qu.Do you know that B.M.R.can give nuisance tripping in hot weather,& interrupt your production & in the cold season it will take longer time to trip?
Qu.Do you know after tripping and rectification of fault you can not run the motor until & unless the bimetal strip cools down (wasting of precious production time)?
Qu.Whatever protection you are getting thru the B.M.R., are they adequate to protect the motor?
Dual saving of Money
1.Since u will get the cause of tripping as soon as fault occurrence.
2. You can save the time to locate the
fault.
3.The chances of damages due to faults other than over load is eliminated.
4. Production loss will be very low.