I bet that the innards are mostly the same with just the dials being different.

Chris Pearson said:

I bet that the innards are mostly the same with just the dials being different.

I would have thought the MFT1835 boards are all the same ... if there are language options, might be firmware or LCD difference?

Even if the 1835 boards are different to the 70 and 1700 series, they will be based on a similar design theme no doubt, as core elements are the same.

I meant to say just the dials and software. It wouldn't surprise me if the cheaper models with fewer features simply had them disabled. Manufacturing multiple PCBs and switches may cost more than using the same, although the PCBs of the cheaper models may not be fully populated with liquorice allsorts.

I'd agree, if it was the sort of thing that we design, we'd just have a different firmware/prom load and the specific case artworks would be stickers, perhaps varying the internal wiring loom to country specific connectors. 

Unless there are really expensive parts on the BOM the expense of stocking 2 or more versions of the PCB is not normally justified. The other way is to have a main board that does not change and plug in 'daughter card' for the variants.

Actually Worcester Bosh take  that idea almost to the limit, and have a PCB that fits several models, and just a 'code plug' that is just some resistors on a plug the size of an acorn, the micro-controller reads the voltage division (oh for micro controllors with an on-board ADC, with 1% resistors,  many possible distinct states on one pin ), and runs the code appropriate to a specific model of boiler, but all the code options are pre-loaded.

I cannot see anything in a  typical MFT that is so expensive or different between destinations as to need much of a redesign..

Mike.

I'd agree, if it was the sort of thing that we design, we'd just have a different firmware/prom load and the specific case artworks would be stickers, perhaps varying the internal wiring loom to country specific connectors. 

Unless there are really expensive parts on the BOM the expense of stocking 2 or more versions of the PCB is not normally justified. The other way is to have a main board that does not change and plug in 'daughter card' for the variants.

Actually Worcester Bosh take  that idea almost to the limit, and have a PCB that fits several models, and just a 'code plug' that is just some resistors on a plug the size of an acorn, the micro-controller reads the voltage division (oh for micro controllors with an on-board ADC, with 1% resistors,  many possible distinct states on one pin ), and runs the code appropriate to a specific model of boiler, but all the code options are pre-loaded.

I cannot see anything in a  typical MFT that is so expensive or different between destinations as to need much of a redesign..

Mike.