Sontex Supercal 531

Hardware
1

Ive been asked to look at what happening with a heat pump that has this in the cylinder cupboard. Is it possible to integrate this with an emonpi?

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2

Potentially. It will depend whether that specific example of a Supercal 531 was purchased with the optional M-Bus (Meter-Bus) interface installed. If that’s present then you’re all good - other people have successfully interfaced the 531 using M-Bus.

(I note it includes the word “BUS” on the label with the barcode, which is promising, but I’m not familiar enough with this model to know whether that means Meter-Bus, MODBUS (which is different) or something else.)

If it doesn’t have the M-Bus interface present then it might be possible to retro-fit that - or to connect using a different protocol.

Best thing is to get the cover off and check for a pair of terminals labelled “M-BUS” or similar.

3

FWIW, the Sontex manual mentions only M-Bus.
I couldn’t find any reference to Modbus.

sontex_supercal_531.pdf (2.3 MB)

4

There’s certainly an optional Modbus interface card available for the Supercal 531, but perhaps that’s never factory-fitted: https://sontex.ch/wp-content/uploads/2019/02/supercal531-modbus-ig-en.pdf

5

All Sontex 531s have MBUS as standard, it’s integrated into the main board. I’ve successfully connected quite a few of them via MBUS. Modbus is an optional interface board.

This emonhub interfacer will work to read data via MBUS, the default MBUS ID is usually 1 or 0.

[[MBUS]]
    Type = EmonHubMBUSInterfacer
    [[[init_settings]]]
        device = /dev/ttyUSB0
        baud = 2400
    [[[runtimesettings]]]
        pubchannels = ToEmonCMS,
        read_interval = 10
        validate_checksum = False
        nodename = MBUS
        [[[[meters]]]]
            [[[[[heatmeter]]]]]
                address = 1
                type = sontex531
6

Thanks for all the helpful advice.

7

Hence my FWIW and the inclusion of the user manual, which made no reference to Modbus. But, as you’ve pointed out, it certainly could be installed.