[FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

[redwire]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

That's really weird. I wonder if it could be something enabled or disabled in settings that are stored in the EEPROM. Does it remember the temperature setting when you power it off? I'd poke around the menus if it has any.

Otherwise, the only fix would be an MCU adapter board that people have made for these.

[jmbinette]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

I think what redwire is saying, is that Pin 18 may not be the pin the firmware is actually expecting the sleep signal on. As far as the software is concerned, Pin 18 may not even exist - the software might be waiting to see that sleep signal on say, Pin 17 instead.

Or, the software might not even have a sleep function at all!

I tried every input pin with a jumper (both high and low) without any success of finding "the hidden input"

Seems like the device was not programmed with a standby mode but the manual says clearly that it has one ...

I bought the first unit, returned it and now this one has the same problem. I wondered if I could repair it easily but seems like I will also return this 2nd piece of Chinese cr*p !!

[Agent24]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

I re-tested everything and pin 18 on the IC is really switching from 5V to 0V(Wand on the holder)

I think what redwire is saying, is that Pin 18 may not be the pin the firmware is actually expecting the sleep signal on. As far as the software is concerned, Pin 18 may not even exist - the software might be waiting to see that sleep signal on say, Pin 17 instead.

Or, the software might not even have a sleep function at all!

[jmbinette]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

Are you positive you have the right MCU pin?
The reed switch sees the magnet only when in the cradle, so it closes and I/P goes from 5V to 0V.

The chinese are trying to put hardware copy-protection in their soldering stations, as they steal firmware from others. To prevent cloning, the firmware guy will move an I/P pin so the clone pc boards no longer work. Small chance but this might be what you're seeing.

For the record, here is another PCB to add to the "clones database" ! lol

I re-tested everything and pin 18 on the IC is really switching from 5V to 0V(Wand on the holder)

[redwire]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

Are you positive you have the right MCU pin?
The reed switch sees the magnet only when in the cradle, so it closes and I/P goes from 5V to 0V.

The chinese are trying to put hardware copy-protection in their soldering stations, as they steal firmware from others. To prevent cloning, the firmware guy will move an I/P pin so the clone pc boards no longer work. Small chance but this might be what you're seeing.

[stj]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

only a software function - try picking it up, putting it back, then waiting.
they do have a delay.

[jmbinette]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

if the cpu pin is changing between 5v and 0v when you put the handle on the holder then the cpu is bad i imagine.
otherwise you need to check the reed isnt cracked etc.

I received a second unit from amazon with the same behavior... weird !

And yes the cpu pin is changing between 0V and 5V.
Anything would prevent the cpu from triggering the input?

[stj]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

if the cpu pin is changing between 5v and 0v when you put the handle on the holder then the cpu is bad i imagine.
otherwise you need to check the reed isnt cracked etc.

[jmbinette]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

The triacs (BTA16-600B) are known to short circuit and the heater stays stuck on. Very dangerous and will burn down your house! Never leave these cheap chinese stations plugged in all the time, I pull the power cord after I am finished.
The triac does need a heatsink, so make sure you have one or it will just overheat and short.

The exact 858D schematic depends on your PCB version. Post pictures if you are not sure. This is 858D+ schematic which is similar.

The standby function isn't working, but that doesn't , mean the Triac is shorted.
It heats properly to whatever temperature I set and then maintains it.

[redwire]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

The triacs (BTA16-600B) are known to short circuit and the heater stays stuck on. Very dangerous and will burn down your house! Never leave these cheap chinese stations plugged in all the time, I pull the power cord after I am finished.
The triac does need a heatsink, so make sure you have one or it will just overheat and short.

The exact 858D schematic depends on your PCB version. Post pictures if you are not sure. This is 858D+ schematic which is similar.

[jmbinette]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

not much to it if it matches either of these:

Actually it matches this schematic (resistor and cap ID are different but circuit is the same.

[stj]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

not much to it if it matches either of these:

[jmbinette]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

so your saying the standby function isnt working, but it heats to whatever temperature you set?

That is exactly right

[stj]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

so your saying the standby function isnt working, but it heats to whatever temperature you set?

[jmbinette]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

Whatever controls the heater, probably a Triac, may be shorted?

I originally thought about it but it controls according to temp setpoint. This part seems to work.

[Agent24]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

Whatever controls the heater, probably a Triac, may be shorted?

[jmbinette]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

Hi to all,

I have a Sigma R700 (858D clone) and would like to repair it.

PCB is marked SBK858D 2017.01.03

The heater is always ON no matter it is on the holder or not. I troubleshooted the whole circuit and the reed switch is good.
On microcontroller input P0.1, I get 5V when off the holder and 0V when on the holder.

Am I missing something here ? Any other conditions in the firmware would keep the heater ON all the time ?

Thanks !

[stj]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

what is the soldering like?

some of the chinese units are terrible and you need to resolder most of the board!!!

[Agent24]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

Perhaps the trimmer has broken when you adjusted it? Check the solder did not break on the leads or something.

[jimic12]

Re: [FAQ] Atten 858d problem S-E (or 5-E) or stuck in 498'C.

Hi, mime give me an "Err", that meas de coil is broke, but is not.
This happend after I move the "CAL" trimmer, so I put it back in the same position and nothing happen.
What do you think it could be?

Greetings