Cash register POS need own circuit, "clean power"?
- Thread starter mattri
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- Location
- Massachusetts
I do a lot of POS work and it is typical to supply them from s dedicated panel for computer power often supplied via its own transformer.
That said I know of a great many using 'dirty power' and I don't see any problems arising.
It seems more like a habit carried over from when POS systems used data cables that included a ground reference such as coax or IBM connectors.
Now with cat 5 or 6 cabling it seems unneeded.
That said I know of a great many using 'dirty power' and I don't see any problems arising.
It seems more like a habit carried over from when POS systems used data cables that included a ground reference such as coax or IBM connectors.
Now with cat 5 or 6 cabling it seems unneeded.
I've installed, altered, upgraded, etc. more of these than I care to admit, over perhaps a seven state area, and have run into all kinds of configurations. The trend at the time was to put 'em all on IG circuits. Not the case so much any more.
The truth of the matter is, all they need is a regular outlet. Anything beyond that is for reliability. Basically, the store managers don't want any more than one register going down as a result of a branch-circuit fault. Some of how that is implemented is based on superstition or myth.
The truth of the matter is, all they need is a regular outlet. Anything beyond that is for reliability. Basically, the store managers don't want any more than one register going down as a result of a branch-circuit fault. Some of how that is implemented is based on superstition or myth.
dfmischler
Senior Member
- Location
- Western NY
- Occupation
- Facilities Manager
And there is the tendency of the POS system vendor to start pointing fingers at things he isn't responsible for (e.g. power, grounding, network cables, Internet connection or phone lines) when his stuff isn't quite working. I had one a few years ago that told me his unit wasn't working because the power was "dirty". I set up enough test equipment to convince him the power was OK so he dug deeper. Eventually he found the bad battery-backed RAM module... Typical.
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big john
Senior Member
- Location
- Portland, ME
There's billions of dollars of industry in this country running on computers plugged into standard convenience receptacles, but for some reason POS folks seem really particular about how registers get power: I commonly see little stand-alone isolation transformers powering this equipment when no fancy "clean IG power" is available.
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
This was a long time ago so things might have changed, but I helped on a study done by Costco on their POS system failures. They had a big problem because they insisted on buying used machines, so they were already compromised. They had a facility outside of Seattle that was essentially a bone yard where a crew of techs stripped good parts out of failed registers to make other ones work. It was amazing how much time and effort they spent trying to get away with used stuff, yet the data from their POS system was incredibly critical to their operation. They bought ferroresonant power conditioners for all of their register stands and cut the failure rate in half.
We later did a time and motion study on one of their average stores for the purpose of determining if it was worth it to upgrade to UPS systems so that if the power failed, they could at least finish the transactions in process and maybe a few more with 10 minutes of backup power. With 36 registers running they were moving almost 200 transactions per hour through there, each one an average of $130 (this was in 2001 I think). So every time power went out, they were losing $5400 in immediate transactions, upward of $20K if they could finish more. Turned out they were too cheap to install backup generators too, plus they used the cheapest minimum emergency exit lights, so if power went out they had to clear the store in 10 minutes anyway and the $5400 recovery was irrelevant to them.
We later did a time and motion study on one of their average stores for the purpose of determining if it was worth it to upgrade to UPS systems so that if the power failed, they could at least finish the transactions in process and maybe a few more with 10 minutes of backup power. With 36 registers running they were moving almost 200 transactions per hour through there, each one an average of $130 (this was in 2001 I think). So every time power went out, they were losing $5400 in immediate transactions, upward of $20K if they could finish more. Turned out they were too cheap to install backup generators too, plus they used the cheapest minimum emergency exit lights, so if power went out they had to clear the store in 10 minutes anyway and the $5400 recovery was irrelevant to them.
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