I think I’m correct in saying the switched live in a 2-point actuator is only really energising the coil of the actuator’s internal relay, rather than the motor directly (unlike 3-point control with two switched lives). This then switches the direction of the actuator/motor fed from the permanent live, so the load the CT sees on the switched live maybe lower than the motor rating and may be too low to detect, but as Robert suggests, looping it through the CT may do the trick?
Apologies for jumping in on this. I am looking to do something similar to a relay feed rated at 2W. Wouldnt like to squeeze more than 4 coils.
What size wire is that? For a 2 W relay at 230-250 V, you only need something like this: https://uk.rs-online.com/web/p/hook-up-wire/1964211 The overall diameter is 1.3 mm. From memory, that should be good to at least 2 A, so a safe rating with many turns bunched would be around 1 A (about 100 times the current you have).
That was 1.0 flex. the relays are RS 348-762 10A dpco and RS 348-813 13A 3pco.
setup could be described as bespoke typical as my wife would say…
house controls schematic.pdf (83.2 KB)
the black flex on the left hand side is the feed to the hot water diverter valve from the vaillant heat pump control interface. with just the single cable the reading just about works.
will try with a couple of turns later.
is there a simple way to get this to an on/off signal to feed in to the heat pump app?
You need to ask somebody else - I know nothing about the heat pump monitor.
As I pointed out a long way up this thread, measuring the current drawn doesn’t give you a foolproof indication of the state of the valve, though it might be more reliable for a relay (it’s less likely to jam).
Ah that’s an ESBE valve, these valve only draw current when moving from one state to the next. Therefore, it’s not possible to use the CT detection method. We now have an optoisolator alternative sensor available which will detect the 240V signal directly from the switched live, rather than measure the current. Please contact the shop to arrange delivery of this alternative sensor: [email protected].
Sorry for the hassle.
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Thank you Glyn for finding and delivering a solution for emonHP DHW monitoring in my configuration.
For others new to this thread, my install uses a 3-way valve which is actuated by an ESBE ARA655 motor. This actuator can’t be monitored using a c.t., but it can be by wiring the optoisolator sensor that OEM recently supplied to me across the switched live, in parallel with the motor input.
This is working reliably down a 10 metre length of cat5 cable to the Pi2. I used 6 cores in 3 of the twisted pairs - one colour pair each for gnd, 3.3v input, and logic out.
I’m using the 4th pair for the c.t. which is around the live of the surplus PV sent to the immersion element.