Author Topic: Want to moniotr all 40 circuits on panel  (Read 2337 times)


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Want to moniotr all 40 circuits on panel
« on: April 13, 2017, 07:25:20 AM »
I just purchased the MTU with 2 spyders: I have 40 circuits on my 200a panel. since an mtu can only monitor 16, how can i effectively monitor all the circuits on my panel?
Also, I have a few cts that are showing 0 power.  What is the threshold for a 20A ct or 40A ct?


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Re: Want to moniotr all 40 circuits on panel
« Reply #1 on: April 13, 2017, 10:14:38 AM »
A second MTU, with another two Spyders, will give you another 17 monitored circuits (the MTU's CTs can monitor a 240V load circuit - it doesn't have to monitor utility power or generation), at substantial increased cost, but you are then out of options for further expansion with the TED system. I think, however, that you need to think seriously about whether you really need routinely to monitor all 40 circuits, and about whether you will really look at all that data on an on-going basis. If your interest is in conserving power, the big bucks are in usage for HVAC, cooking, and (at least in my case!) computer-related loads. Everything else is pretty small beer. While you may conceivably want to do an initial survey of power usage on a circuit by circuit basis, perhaps to catch unexpected vampire loads, this can be done by using a few Spyder legs to monitor the lower power ones on a rotating basis for a week or so at a time.

The Spyder specs are to be found at The power threshold rating for the 20A CT is 60W (~ 0.5A) - that for the 60A and 200A is 200W (~ 2A).
Peter R. Fletcher
TED Pro Home - main MTUs monitoring utility and PV Solar feeds; 2 Spyders monitoring selected individual circuits