Feedback: Product line dimensions vs. german cabinet standards and integration densit

[mkai]

Hey there, 

First: I find the Kinkony products very compelling and find it amazing what product lines you built always following the open approach of open hardware with schematics and software support for ESPHome!

I want to use several actors in my future house to control 230V and Roller/Shutters with ESPHome, but there are some drawbacks preventing me. I'd like to share my thoughts - maybe for your future products

- The actors should be installed in a "standard german electrical cabinet" following the standard "DIN 43880:1988-12".
- This standard defines division units (DU) of 17.5mm for DIN-rail devices. The standard cabinet provides a width of 12 DU (12x 17.5 = 210mm) per slot.
- All common smart home devices in Germany follow these standards, e.g., HomeMaticIP Wired, Loxone and KNX. These units are available in 2, 4, 6 or 12 division units to maximize the space utilization in cabinets and provide around 1 relay per DU.
- For my Smart Home, I need a bunch of 230V actors supporting 10A (roller shutter) and 16A relays (switchable sockets / lights) and don't have much space left in the existing cabinets, so integration density is crucial.


- Your product line:
-- I find the F16 very compelling, but it exceeds the maximum width of my cabinet slots (262mm F16 vs. 210mm (12DU) cabinet). Costs are ~15 USD/relay.
-- The F8 on the other hand would fit with its 195mm, but only provides a overall poor integration density of 8 relays / 12 DU and has a higher cost per relay (~20 USD/relay).
-- KC868-A8v3 comes with 8x 10A relays, width: 148mm(9 DU), integration density: 8 relays/9DU;  costs: 8USD/relay
   Q: Can't find the schematics for the v3 version. Is there a single PCB variant supporting V12 and V24 power supply (as opposed to the v1 versions where the relays are either 12V or 24V)


--> My conclusion: At the current state none of the products really match by requirements, so I want to share some thoughts:


Summing up my requirements for the ideal cabinet 230V actor:
- 24V power supply
- Device width following 6 or 12 DU DIN Rail widths
- LAN connection (POE would be nice, but 24V power is also available in the cabinet)
- 23V outputs: 10 / 16 A relays
- Inputs: Every relay should have one corresponding opto-coupled dry contact input (24-capable)
- Stand-only functionality: Should work without active connection to the home controller / home assistant.
- High integration density: 1 Relay per 1 DU (17.5mm) as provided by competitors (Loxone, Homematic, KNX)
- NO need for additional interfaces (CAN, Tuya, SDCard, analogue in, etc.).
- costs should not exceed 15USD/ relay
- Housing with proper cover is a must. LEDs should indicate active relays. A display does not matter. An additional RGB-LED showing a general device health-status (power okay, ESPHome connected/disconnected) should be enough. 


Additional (unstructured) feedback:
- I like the idea of having input overrides as the switches in the F-series. But for using them as a roller-shutter actor this can lead to severe problems (powering both up -and down of the roller-shutter at once). While accessing the device by software there will be an mutual lock of Up/Down ESPHome (already provided in their sources).
Could you consider replacing the "permanent switches" with buttons and program a software-behaviour like "hold them for momentary-override" or "double click for permanent on/off"?
- The connectors used in your products are rather large. Could you consider using connectors with a smaller footprints? The reduced size could be used for additional relays on this side of the board (especially good for 12 DU units (6 DU for inputs/power and 6 DU for 4 additional relays).
- Did you know that the company Waveshare (e.g., Modbus POE Eth Relay ©) has a nice concept of DIN-rail devices with 2xEthernet/RJ45 POE-in and POE-out? This allows for device chaining, which is super cool for tight cabinet spaces
- Product selector:
-- Please make separate a selection for 12V and 24V.
-- Filter by size / length

My background: Electrical Engineer (PCB design / FPGA). Designed several Atmega 328-based devices for my cabinet and want to upgrade for better HomeAssitant integration. I have many more ideas and would be happy to discuss, if you are interested


Best Regards, sorry for the long post and keep up your good work!

Martin

[admin]

Thanks for your suggestion.

1. KC868-A8v3 power supply both support DC12-24V. it use by 5v relay coin.

2. you said: "Summing up my requirements for the ideal cabinet 230V actor:"
what's "23V outputs: 10 / 16 A relays"? Do you want DC23v output terminal?

3. Could you consider replacing the "permanent switches" with buttons and program a software-behaviour like "hold them for momentary-override" or "double click for permanent on/off"?

--> Now the digital input ports use by wall switch buttons. manual control button use by "permanent switches", because of it can work without firmware or software, so that any time it can control relay on/off physically, because it control relay's coin directly.

[lulu01]

Hello Martin,

You could also use H32B Pro boards, and use them to drive external very slim relays, for instance the Finder 93.61.7.024 relay holder is only 5 mm wide, so you could easily use one rail for the board, and one rail for 32 external relays. Wiring would be probably cumbersome though.

But I agree, I used to have Dovit relay boxes, and you can fit two 8-relay boxes on one rail, this is very convenient.