Oddbean

I guess the power consumption of such a device would be quite low, I can imagine wiring in a small battery and solar panel to create a portable off grid version 😁 I love these sort of projects, Kudos to all involved!

It’s powered through a 12V power supply. The WT32-SC01 is 240mAh. The NV10USB+ bill acceptor has a standby of 0.2A and running of 1A. The DG600F(S) Multi Coin Acceptor has a standby of 50mA and max running of 450mAh. I haven’t done the sums myself, but assuming on standby and running for 30 minutes a day: To determine the battery and solar power requirements for your setup, we need to calculate the total energy consumption of the system and then size the battery and solar panel accordingly. ### Energy Consumption Calculation 1. **Power Consumption in Standby Mode:** - **WT32-SC01:** 240mA - **NV10USB+ Bill Acceptor (Standby):** 200mA - **DG600F(S) Coin Acceptor (Standby):** 50mA - **Total Standby Current:** 240mA + 200mA + 50mA = 490mA 2. **Power Consumption in Active Mode (for 30 minutes per day):** - **WT32-SC01:** 240mA (unchanged) - **NV10USB+ Bill Acceptor (Active):** 1A - **DG600F(S) Coin Acceptor (Active):** 450mA - **Total Active Current:** 240mA + 1000mA + 450mA = 1690mA = 1.69A 3. **Daily Energy Consumption:** - **Standby Time per Day:** 24 hours - 0.5 hours = 23.5 hours - **Standby Consumption:** 0.49A * 23.5 hours = 11.515 Ah - **Active Consumption:** 1.69A * 0.5 hours = 0.845 Ah - **Total Daily Consumption:** 11.515 Ah + 0.845 Ah = 12.36 Ah ### Battery Sizing To ensure reliable operation, it is common to size the battery to provide at least 2-3 days of autonomy (no solar input), and to prevent discharging below 50% to extend battery life. - **Required Capacity for 2 Days Autonomy:** 12.36 Ah/day * 2 days = 24.72 Ah - **Considering 50% Depth of Discharge (DoD):** 24.72 Ah / 0.5 = 49.44 Ah So, a **50Ah battery** would be a suitable choice to ensure reliable operation with some margin. ### Solar Panel Sizing To size the solar panel, consider the total daily energy consumption and the average solar insolation (sunlight hours) in your location. Let's assume you have an average of 5 peak sun hours per day. - **Daily Energy Requirement:** 12.36 Ah/day * 12V = 148.32 Wh/day - **Required Solar Panel Power:** 148.32 Wh/day / 5 hours/day = 29.66 W To account for inefficiencies and potential losses, it is advisable to oversize the solar panel by about 25-30%. - **Adjusted Solar Panel Power:** 29.66 W * 1.3 = 38.56 W So, a **40W solar panel** would be appropriate to reliably charge the battery and power the system. ### Summary - **Battery:** 50Ah 12V battery - **Solar Panel:** 40W 12V solar panel These components should provide sufficient power to run your system, considering both standby and active periods, while ensuring a reliable and sustainable power supply.

Very nice! What's your primary use case for this device? This is the first time I've encountered it but I love the concept! I can imagine it being posted at a community market to enable Bitcoiners to easily withdraw cash for the traders who are still no-coiners. And due to the privacy of cash and lightning this is great 👌🏼

Aaah I see! It's for buying sats, not selling, got it 👌🏼 I can imagine more use cases for a sats to cash version of the machine due to all retailers already accepting cash (is that something we might get in 5he future?), but I guess if a retailer is interested in hosting a machine like this they will probably just accept sats anyway making that kind of machine redundant... but this cash to sats version is surely better for driving adoption 👍🏻 I love to see this kind of innovation 👍🏻

A machine that could do both would be pretty cool! This would need a cash recycler (accepts and dispenses). Although depending on demand might be more of a security concern as more cash sitting in it.

It would definitely be a higher risk target, but I guess if it's secured within a business and left emptied and visibly open every night the risks could be minimized as with conventional ATM's. I would love to see these appearing in my local convenience stores! 😅 have you looked into the legality of hosting these devices?

Whoever is running it could set up alerts to just go empty it whenever amount taken reaches a certain value. In terms of legality, I think *technically* you need a money transmitter license in the UK - although at the same time they say #Bitcoin isn’t money - so not sure. I think however, for small amounts to friends and family that’s ok. Technically you could run these in stealth mode as no KYC to run a node that dishes out the Sats with the operator unknown?! ;-)