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  1. #1
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    Toshiba Inverter Problem



    Guy's
    I've got a Tosh Rav...about 6kW...R410a....can't recall exact model at the mo, which keeps on shutting down after approx 5 minutes.
    I've traced the fault to the compresser not being happy as it is ramped up to 266hz.!!!!
    Anyone know what the maximum hz should be?
    At 223 hz the amp draw is 8.4 so it's not over current
    Discharge target is 100C but it is only around 69C when it shuts down



  2. #2
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    Re: Toshiba Inverter Problem

    Quote Originally Posted by frank View Post
    Guy's
    I've got a Tosh Rav...about 6kW...R410a....can't recall exact model at the mo, which keeps on shutting down after approx 5 minutes.
    I've traced the fault to the compresser not being happy as it is ramped up to 266hz.!!!!
    Anyone know what the maximum hz should be?
    At 223 hz the amp draw is 8.4 so it's not over current
    Discharge target is 100C but it is only around 69C when it shuts down
    Hi Frank, are you sure that's right, 266hz seems unusually high.
    I know it's a different manufacturer but city multis only ramp up to a max 113hz.

    Could it be a low discharge superheat fault?

    I'll look in my manuals later to see if I've got any info on the max compressor hz if no one else has posted.
    Last edited by marc5180; 30-03-2014 at 09:24 PM.
    The difference between genius and stupidity is that genius has its limits.

    Marc

  3. #3
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    Re: Toshiba Inverter Problem

    Exactly Marc...Daikin only go to 189 hz or so.

    My hz clamp doesn't lie... ��

  4. #4
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    Re: Toshiba Inverter Problem

    Just out of interest, what's the discharge at and what mode was it running in?
    The difference between genius and stupidity is that genius has its limits.

    Marc

  5. #5
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    Re: Toshiba Inverter Problem

    Heating mode, discharge temp at cut out was +68C...target is 100C according to the service manual

    Full model number is RAV-SM802AT-E

  6. #6
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    Re: Toshiba Inverter Problem

    As you probably know, It doesn't seem to show the Hz for some reason but rather the rps of the compressor. At 8.4 amps it's roughly 75 rps but in heating mode this can go up to 120rps which consumes 14amps so going off them figures suggest it's only running about 60%.

    It does say 'the compressor Hz measured with a clamp meter is 2 times the revolutions (rps) of the compressor'

    Even so, that's still a long way off 223Hz.
    The difference between genius and stupidity is that genius has its limits.

    Marc

  7. #7
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    Re: Toshiba Inverter Problem

    Yep..got that already. On the graph for the compressor, it shows maximum 120rps @ 14A, so taking Hz to be (rps x 2) it looks like the compressor maximum rpm = 7200. At 266hz, (133rps) it seems to be pushing the compressor outside of it's envelope (7980 rpm) at 60% capacity

    The sound it makes seems to confirm this.

    Spoke to Tosh Tech this morning, he seems to agree that it is the inverter pcb at fault but suggests we megger the compressor first to make sure that it is healthy.

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