According to Stefan Trethan the connections on the JBC T245 tips are different than previously stated.
According to his findings, on this tips the thermocouple is between the outer sleeve and the inner contact, so if the inner contact is connected to the pulsed (PWM) 24v rail the iron tip will have approximately the same voltage (difference will be the TC voltage).
This will make things go boom if ground is connected to chassis ground, as suggested in order to use the stand sleep function. Even if this isn’t used, having the iron tip with such a large voltage is not ideal either.
The workaround Stefan found is to separate the TC reading from the heater element supply. This is achieved by cutting the trace from the output of the mosfet (as shown on the picture below. The inner contact of the tip is then connected to terminal 4 of the plug (the one connected to C7 and R8), the middle contact of the tip is connected to the output of the mosfet, and the outer sleeve is connected to ground.
Thanks Stefan for finding, reporting and fixing the issue!
On the subject of tips, genuine T12 Hakko tips seem to be a bit difficult to source here at the moment, but T15 are more readily available and are apparently a slot in replacement.
Yes I checked the Hakko website and I gathered the T12 / T15 difference was geographical marketing. The marketing chaps decided they needed different pricing in the US so they called the T12, a T15 and changed the price. T15 for US Canada and T12 for the rest of the world, size exactly the same.
https://www.hakkousa.com/products/soldering-iron-tips/t15-series/t15-d24.html
Hi,
im planing to update my soldering stations.
I’m thinking about JBC stations but price is little bit to high for me and specially that i will need to buy two stations.
I’m considering STM32 station (with black aluminium handle)
https://www.aliexpress.com/item/KSGER-OLED-Soldering-Station-T12-ILS-Electronic-Iron-Tools-STM32-2-1S-Temperature-Controller-Handle-Stand/32825087311.html
I’ve found that firmware update that give possibility of using JBC tips.
Main question is, is there advantage using that station with JBC tips ?
I’m asking cos i’m planing to use that handle:
https://www.aliexpress.com/item/ESD-DI3000-75W-soldering-handle-station-parts-T245-handpiece/32817321335.html?spm=2114.10010108.1000013.1.3dc83416jVEyW3&gps-id=pcDetailBottomMoreThisSeller&scm=1007.13339.90158.0&scm_id=1007.13339.90158.0&scm-url=1007.13339.90158.0&pvid=72e3f16a-3793-4c13-8e09-000b3cfcec84
with that tips:
https://www.aliexpress.com/store/product/10-pieces-lot-Sn-Pb-63-37-0-5mm-500g-roll-solder-wire/805067_32572251088.html?spm=2114.12010612.8148356.31.617e31b7I1zkbg
Asking cos i’m mainly soldering RG402 cables to 2oz pcb’s and to connectors. I also work with aluminium pcb’s.
Doing it with stations that uses 900 tips it’s very slow and usually i must work with 450 degrees.