We have had good stock of these since before the current shortage.
The PCB prototypes for the emonPi and rfm69pi designs I mentioned above have arrived and I’ve had a chance to complete the assembly, here are a couple of pictures of what these look like:
EmonPi v2.0
This would fit inside a Lincoln Binns U-case with acrylic fascias:
Electronics Case - U-Case Range | Lincoln Binns Ltd
RFM69Pi - Terminal block option
RFM69Pi - CT jack sockets and voltage sensing option
The next step is to do work on firmware and testing of enclosures for these.
Looks good 
Is it still open source hardware?
Another progress update.
Robert Wall developed a new set of firmwares for the EmonTx v3 and emonPi, published last year (see forum post here). I’ve adapted these firmwares to run on the EmonTx4 and emonPi2 providing continuous monitoring + native RFM69 radio support on the new hardware and uploaded the firmwares to the emonTx4 and emonPi2 github repositories. There is also a short guide in each repository on setting up the Arduino IDE, downloading the right libraries and setting the compilation settings.
See the guide for the emonPi2 here
emonpi2/firmware at main · openenergymonitor/emonpi2 · GitHub
and the guide for the emonTx4 here:
emontx4/firmware at main · openenergymonitor/emontx4 · GitHub
The OLED display firmware for the emonPi2 is coming together nicely. Here’s a picture of it running on one of the RFM69Pi boards I mentioned above. You can do much more than this with these display’s of course but it can at least do the same as the original emonPi LCD so far.
emonPiLCD script code changes required:
Comparing master...emonpi2lcd · openenergymonitor/emonpi · GitHub
We have also been building up more systems for ongoing development and testing.
We are still waiting on another quote for the EmonTx4 and emonVS manufacture and will hopefully update on that soon.
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please sir!,… any updates…
Thankyou
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Hello @diyhouse
We are running behind on our original estimate, it is now looking like we will have stock of the EmonTx v4 and emonVs, towards the middle of September (approx 6 weeks time). I can also now share what we expect the pricing will be.
The price for the EmonTx v4 looks like it’s going to be £66.25 ex VAT (£79.50 inc VAT). That’s with quite a tight margin with the way costs have been rising across the board. It’s a little more than the current emonTx v3 but with quite a bit more functionality.
emonVs, the precision voltage sensor and power supply is looking like it will be ~£54-59 ex VAT (£65-70 inc VAT) for the single phase version, ~£63 ex VAT (£75.6 inc VAT) for the 3 phase version. This provides a much more accurate voltage reading than the AC adapter’s that we have been using, though unfortunately at a higher price. This is something we will continue to look at over time to see how we can reduce the cost, perhaps with alternative options such as an adapter board for the original AC adapter.
Edit: As a package the EmonTx v4 + EmonVs voltage sensor looks to be about £125 ex VAT (£150 inc VAT) with CT sensors and an emonBase basestation on top of that - or the WiFi option when that becomes available.
@TrystanLea am I right that the V4 needs the emonV?
If so, I’d suggest it would be better to advertise this as a package, rather than as this plus this. Also for retail, you should really quote a VAT inc price 
At that price point, is this an RFM Unit that could be connected via the serial port?
How much for the ESP32 and LCD board?
Thanks @borpin , yes the emonTx v4 does need emonVs, it probably does make sense for it to be a package as you suggest. Yes good point re inc VAT, the thought was that not all of our customers are UK customers though its usually best to quote both prices, I will amend.
Yes it is an RFM unit that can also be connected via the USB C port to a RaspberryPi, is that what you mean?
Still a bit further off on the ESP32 + LCD board, emonPi v2 and the CT extension board. Focus in recent weeks has been on the emonPi v2 and end-to-end system testing, alongside trying to work through a packet loss issue with the RFM69 radio’s.
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Does it make any commercial sense to offer a version without the RFM Chip & Antenna port? I can see a lot of folks using the V4 without wanting the additional cost of an emonBase as well. TBH, unless you are using an emonTH, it makes little sense to pay for a base. If you have multiple units even less so.
Personally, I think the TH has had it’s day with plenty of battery BLE sensors around that are far cheaper.
I think Wi-Fi for the V4 should be the default comms method with RFM as backward compatibility.
Thanks @borpin it’s a good point re rfm options. We have offered no-RF variants in the past, but it is difficult to gauge demand for each variant for manufacture. We are however planning to place greater emphasis on using USB for direct connection between the emontx and a Pi based base station in the setup guides.
The ESP WiFi is great for remote server connected systems but less advantageous for those keen on local data storage. Emoncms.org has its own costs of course, which typically makes local storage cheaper long term especially for complex systems with lots of feeds.
The decision not to offer the ability to mount a PiZ inside now seems odd therefore.
And again. The Pi decision seems odder.
I think the strategy is a little confused.
My understanding was that the PiZ has a limit on how many can be sold per customer (e.g Raspberry Pi Zero 2 W — Cool Components) and also availability is not great: https://rpilocator.com, all out of stock at the moment, though it does look like many have had stock in the last few months. We will contact RaspberryPi to clarify, as we were able to get a limited Pi4 stock directly.
Yes, but the cost difference is astronomical. How about the Pico? Not looked at that in detail. A Pi4 is overkill for emoncms.
Glyn has contacted RaspberryPi to ask, if it’s an option for us to use and we can get stock we will definitely consider it. We did ideally want to continue with Pi3’s given their lower cost but were not able to get stock of those, hence the Pi4’s. It’s hopefully a short term issue until availability improves and a wider set of options open up again.
Pi’s are an issue, I managed to get a ZeroW last year from CPC, ordered another in March and here we are in August still waiting… website says expected May 2023!
I am having quote for new CU and hope to add more granular circuit monitoring in future so the V4 looks great but the dedicated £50 psu seems a bit limiting? Can V4 not be fed from usb and the old £10 ac-ac brick?
Not really - because the emonVs is a universal power supply and a precision voltage monitor- far more accurate than the Ideal 9 V a.c. or equivalent.
For cost reduction, what about putting a ZMPT101B, primary MOV, fuse, primary resistors and secondary resistor plus any EMI bits into a 13A plug top enclosure, for single phase use?
If a plug top enclosure with a brass earth pin and a means of connecting to it could be sourced, then this would also provide the ground for the emonTX4.
Most 5V USB adapters are universal voltage, and one could be used to power the emonTX4. Many homes will have a redundant USB adaptor and perhaps would just need a USB-A to USB-C cable, otherwise a Raspberry Pi4 adapter (£8.10) could be used.
This solution would require two 13A sockets to supply the emonTX4, but this could be achieved from a single socket using a 13A 2 or 3 way adapter.
We have thought to provide this as an option, as long as people are aware it’s less accurate and are happy thats fine. I guess one of the challenges is that it might be with calibration, especially phase calibration. I know we haven’t discussed this between us yet, especially with your work on the new firmware, so it probably needs some more thought and consideration.