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Immersion heater - economy 7 timer wiring

Former Community Member
Former Community Member
Hello,


I have a honeywell st6400c controller and an immersion heater. 

My heater has 2 switches, off and on peak. My concern is that the heating works only with both switches on. Even if its set to trigger at off peak time only, which it does, both switches light up and if I switch off the onpeak one, the heating stops even tho the offpeak is still lit (testing this at off peak hours ofc). Is this correct ? does this not use much more electricity? I was monitoring this and Im sure it goes against the "night" hours, but my worry is that it uses much more power than it should.

Thank you for your advice

Tom
  • Former Community Member
    0 Former Community Member
    Ive even trained myself to be using all appliances over night, resp early in the morning. washing machine, dishwasher, laptop charging etc, all happens during night rate as i think the e7 would be useless without doing so.

    the 1h and 20 minutes makes enough water for shower and general use considering my gf doesnt spend 1 hour in the shower singing lol
  • 0
    I know but thats an 80 amp cable and its not a smart meter, you can see the control neutral going into the meter


    Sparkingchip:
    DBlencathra:

    Never seen that, only switched live, where is it going ?


    E7 smart meters have a a switched neutral controlling the relay.


    Andy B.




     


  • 0
    AJJewsbury:

    I can't vouch for the terminal ordering/position, but the wires to the timeswitch look to be about what I've seen before around here. Meter output goes to a DP Henley, from there L comes back to the timeswitch where it's SP switched to provide the off-peak supply - which goes past the side of the henley up to the CU, N to the CU comes straight from the Henley. I'd expect another L (and probably N) to the CU direct from the henley to provide the 24h supply,  but can't quite see that in the photos (possibly be hidden behind the off-peal tails). The smaller wires are fused down to provide power to the clock and a switched N to prompt the meter to switch recoding between the peak and off-peak registers.


    It might make more sense if we could see the CU(s) and this st6400c - together with any associated equipment e.g. any contactors/relays.

       - Andy.


    My thoughts too, need another pic to clarify


  • 0
    I’ll throw this in to see if someone knowledgeable comments.


    Smart meters controlling appliances using Zigbee WiFi.
  • 0
    Blencathra:
    I know but thats an 80 amp cable and its not a smart meter, you can see the control neutral going into the meter


    Sparkingchip:
    DBlencathra:

    Never seen that, only switched live, where is it going ?


    E7 smart meters have a a switched neutral controlling the relay.


    Andy B.




     






    As opposed to the external clock controlling the meter to change the rate.


    So the whole installation goes onto E7 instead of being split.


  • 0
    This set up was not the best in its day. The feeds to the block from the meter, live to 24 hour supply, live to time clock. ONE neutral lead to the Fusebox, looped to both supplies. All ok as long as the neutral is in the incoming sides in the board.


    Regards, UKPNZap

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