BK Precision 9110 Factory only port - serial?

[slow_rider]

So we have a bunch of BK Precision 9110 power supplies and we need to come up with a way to log their readings. The back of the thing has a D-sub connector, like the ones that are used for RS-232. Connecting a TTL to RS-232 adapter and sending whatever text over the serial will get a garbage response at all the bauds I've tried, but only on the first communication after power-up. The sent chars are also looped back (not hard-wired, does not work when power is off). I have a feeling that there might be a way to read the data from this port but not sure where to start. The motivation is not to exchange all the power supplies we have which would take time and cost a small fortune. I've contacted the company, they claim to have no information. My guess is that this model is rebranded, like other models by BK, since they all look different.

Thoughts?

[bdunham7]

Well they tell you specifically that there is no remote control interface.  The connector appears to be for factory calibration purposes, so I suppose if you had the information you might be able to read out the data.  Maybe.  In any case, try googling around for the ITech IT6720 because I think your unit is based on that.  Perhaps someone has software that works with it in some fashion.  Otherwise you'd need to tear one down and see what that connector is wired to internally.  Someone already tore one down and posted pictures:

https://www.eevblog.com/forum/reviews/bk-precision-9110-60v5a-100w-psu-review-(with-pix!teardown)/msg68996/#msg68996

[slow_rider]

Yes I also tend to think this is a rebrand of a slightly modified (or custom made) PSU by ITECH.

Their website suggests that the communication port it has on the back can be used by the users as well. BK are probably not interested in having this feature at this price point?
Anyway the links do not work and registration in order to download stuff from the website does not work either.

https://www.itech.sh/en/info_128.aspx?lcid=16&itemid=126

[bdunham7]

Yes I also tend to think this is a rebrand of a slightly modified (or custom made) PSU by ITECH.

Their website suggests that the communication port it has on the back can be used by the users as well. BK are probably not interested in having this feature at this price point?
Anyway the links do not work and registration in order to download stuff from the website does not work either.

I didn't see any clear evidence that there is any user software or available protocol for either brand.  I think ITech is owned or related to BK as well.  Not sure of the exact arrangement.  BK is usually pretty good about providing software and support, but if they don't have it they don't have it.  This could be an obscure one-off custom system for calibration that someone dreamed up a long time ago.  I can think of a number of instruments that have DB9 and DB25 connectors but are never going to communicate (generally) with you no matter what you do.

[slow_rider]

The bottom of the page has a link to a communication protocol which seems also to be included on the CD they offer(ed).
What makes me believe this has the ability to read back data is the fact it was probably used for calibration, so one must have the ability to read data from the device and second, it loops back whatever I am sending it over serial. This is done in software because when I power it down it stops returning.