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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
AJJewsbury:
I suspect that in practice this is achievable only with a row of EVCPs along the side of a factory.
So what happens when just some of the charge points are in use? How can balance be assured? After all not all the batteries will be equally discharged or plugged in at the same moment, so they'll disconnect at different times as the cars become fully charged.
Or is the assumption that the EVSE load will be negligible compared to the balanced load of the factory?
- Andy.
Table J1 of the IET Code of Practice for EV Charging Equipment Installation shows the percentage unbalance required, and J4 (page 156) a “rule of thumb” for percentage unbalance, being:
So, perhaps more unbalanced than you might think?
BUT
John Peckham:
I think for the balanced 3 phase option the consumer would need to be a single user on a transformer AND then have a balanced 3 phase installation.
John's point is, that if a number of three-phase installations are supplied by the same combined neutral and earth (CNE) distribution main, then just checking the balance of the installation in which the EV charger is installed won't be guaranteed to protect that installation if a break occurs upstream of a number of installations and the one in question, if one or more installations upset the balance on the distribution main.
The important thing to remember about 722.411.4.1(i) is that it's the balance of the three-phases downstream of the broken PEN conductor in the distribution main, not either a single installation, nor the distribution main as a whole.
AJJewsbury:
I suspect that in practice this is achievable only with a row of EVCPs along the side of a factory.
So what happens when just some of the charge points are in use? How can balance be assured? After all not all the batteries will be equally discharged or plugged in at the same moment, so they'll disconnect at different times as the cars become fully charged.
Or is the assumption that the EVSE load will be negligible compared to the balanced load of the factory?
- Andy.
Table J1 of the IET Code of Practice for EV Charging Equipment Installation shows the percentage unbalance required, and J4 (page 156) a “rule of thumb” for percentage unbalance, being:
So, perhaps more unbalanced than you might think?
BUT
John Peckham:
I think for the balanced 3 phase option the consumer would need to be a single user on a transformer AND then have a balanced 3 phase installation.
John's point is, that if a number of three-phase installations are supplied by the same combined neutral and earth (CNE) distribution main, then just checking the balance of the installation in which the EV charger is installed won't be guaranteed to protect that installation if a break occurs upstream of a number of installations and the one in question, if one or more installations upset the balance on the distribution main.
The important thing to remember about 722.411.4.1(i) is that it's the balance of the three-phases downstream of the broken PEN conductor in the distribution main, not either a single installation, nor the distribution main as a whole.
