Morning everyone. I’m trying to connect two optical pulse counting sensors to an emonTx4. The emonTx is connected to emonBase over USB. The first pulse counter is obvious: straight into the RJ45. For the second pulse counter, I read this: [image] define PULSE_PIN 1 - Other sensors The e…

[image] coltcc: Removing a solder bridge sounds tricky - any tips? do i just pry it off somehow? I don’t solder either, but @Robert.Wall does all the time… [image] Problems with emonTx4 + 6 port CT expansion Ouch! Don’t practice on your emonTx4. Get a piece of stripboard and a ‘grab bag’ …

I strongly suggest, as in the link Sarah provided - practice first, a lot. I’ve never got on with de-soldering braid, but others seem to find it works for them. [image] coltcc: Removing a solder bridge sounds tricky - any tips? do i just pry it off somehow? NO NO NO! You will more than likel…

[image] Robert.Wall: I’ve never got on with de-soldering braid, but others seem to find it works for them. The “trick” there is to either use braid that already has flux in it, or dip the end of the braid in paste flux if the braid you have has no flux. [image] Robert.Wall: I have seen t…

[image] Bill.Thomson: Food for thought. Indeed. The pulse input depends on whatever protection the input pin of the processor has - from memory: none. The temperature input fares only very slightly better - it has a 4.7 kΩ pull-up to 3.3 V.

[image] Robert.Wall: If you’re buying, and if you can afford it, get one that is temperature controlled, and get the smallest bit available (the ‘bit’ is the tip that actually does the soldering), get a small coil of solder and a solder sucker - I use the ‘piston’ type where, when you press a bu…

2x optical pulse sensors with emonTx4

Hardware emonTx

SarahH (Sarah Hanson) 8 May 2026 09:53 2

I don’t solder either, but @Robert.Wall does all the time…

(My emphasis. I’ve watched my partner use one, and it doesn’t look that difficult…)