SINGLE PHASE LOAD SHEDDING

I agree with AJJewsbury, I would be concerned that instantaneously disconnecting equipment like EV charge points, heat-pumps or air-conditioning units with a contactor risks, at worst, doing some damage to the equipment itself or at best, inconveniencing the user from loss of functionality, loss of network connection or settings, issues if the equipment does not re-start smoothly. I would see this solution as a last resort, or rather a final protection measure, a back-up, to be applied if the load cannot be reduced in the first instance using a more sympathetic / graceful method.

There's quite a few models of EV charge point, where if you read through the manuals or supplementary manuals, you can find models which accept external volt-free inputs to shed load, either reducing load to a specific level, or interrupt charging and this is then done gracefully, with the charge-point remaining powered up and communicating with the EV, rather than suddenly dumping the load with the risk to the charge-point and the EV itself. Quite a few models also have dynamic load control, with a CT to monitor load on a supply circuit and dynamically adjust charging to operate within a maximum current limit.

Same with heat-pumps, for example some of the Daikin models, either come with or can be fitted with a daughter control board, which accepts a range of Smart Grid inputs, for power limitation in multiple configurable steps, so power demand can be adjusted to manage load. Again, a graceful approach which keeps the equipment running with equipment ramping down the compressor in a controlled way, rather than dumping the load.

I think this approach could give a relatively seamless experience for the user, even if you were regularly activating the demand control function, whereas the contactor/load-switching approach would be a lot more bumpy and inconvenient for the user.

I agree with AJJewsbury, I would be concerned that instantaneously disconnecting equipment like EV charge points, heat-pumps or air-conditioning units with a contactor risks, at worst, doing some damage to the equipment itself or at best, inconveniencing the user from loss of functionality, loss of network connection or settings, issues if the equipment does not re-start smoothly. I would see this solution as a last resort, or rather a final protection measure, a back-up, to be applied if the load cannot be reduced in the first instance using a more sympathetic / graceful method.

There's quite a few models of EV charge point, where if you read through the manuals or supplementary manuals, you can find models which accept external volt-free inputs to shed load, either reducing load to a specific level, or interrupt charging and this is then done gracefully, with the charge-point remaining powered up and communicating with the EV, rather than suddenly dumping the load with the risk to the charge-point and the EV itself. Quite a few models also have dynamic load control, with a CT to monitor load on a supply circuit and dynamically adjust charging to operate within a maximum current limit.

Same with heat-pumps, for example some of the Daikin models, either come with or can be fitted with a daughter control board, which accepts a range of Smart Grid inputs, for power limitation in multiple configurable steps, so power demand can be adjusted to manage load. Again, a graceful approach which keeps the equipment running with equipment ramping down the compressor in a controlled way, rather than dumping the load.

I think this approach could give a relatively seamless experience for the user, even if you were regularly activating the demand control function, whereas the contactor/load-switching approach would be a lot more bumpy and inconvenient for the user.