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Has anybody used these matt-e products for EV charging points?

Former Community Member
Former Community Member

Is this brand any good ? 

The supply source is a three phase T-N-C-S system. The load on the three phase distribution board is never going to be fully balanced so the options are to either to install earthing rods (electrode) or use one of these devices to avoid hammering rods to be compliant.

Just wondered if anyone had any experience with the brand.

Any other ideas also welcomed.

Regards,

J

 

Parents
  • If you have all 3 phases present, loaded or not,  you can create a pseudo-earth at the junction of 3 equal reactances one fed from each phase. 3 small capacitors Y normally does the trick.

     Some simple electronics can look at the offset between that pseudo-earth point and the supplied CPC or neutral (or both) and raise an alarm or fire a shunt trip as required if the offset goes outside expected limits.

    Such a detector  circuit also operates if the earthing is fine but the 3 phase voltages are badly out of whack, e.g. something like one phase is at less than ⅔ of the voltage of the others,  but disconnecting that condition is probably not such a bad thing either.

    Mike.

     

Reply
  • If you have all 3 phases present, loaded or not,  you can create a pseudo-earth at the junction of 3 equal reactances one fed from each phase. 3 small capacitors Y normally does the trick.

     Some simple electronics can look at the offset between that pseudo-earth point and the supplied CPC or neutral (or both) and raise an alarm or fire a shunt trip as required if the offset goes outside expected limits.

    Such a detector  circuit also operates if the earthing is fine but the 3 phase voltages are badly out of whack, e.g. something like one phase is at less than ⅔ of the voltage of the others,  but disconnecting that condition is probably not such a bad thing either.

    Mike.

     

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