Rmiller
Member
I purchased a 300 watt UPS from Office Max for $60.00 installed it in a remote pump station control panel that has a AD PLC, radio (for communicaton) and ultra-sonic level control. I thought this would be a cheap way to provide data (tank level etc.) for at least an hour or so during a power failure.
The problem with this I have come to find out is that the UPS battery output on most of the cheaper units is a step wave (square wave) that will not provide enough voltage for the plc to see a 120v input, the battery output will only read 80 to 90 volts on a volt meter even though the spec's on the UPS read 115v +/- 8%.
The UPS that I bought was an APC and after talking with their tech support was told that I would have to buy the more expensive one for about $320.00 to do the job correctly and that is would be larger in physical size which is harder to fit in the panel. I was told by a friend that PK electronic's out of Arizona made one for around $100.00 that would do the job (called the Blackout Buster) but I have now found out they are out of business at least temporarily.
Would anyone have any suggestions for where I could find a UPS that provides true sine wave for around $100.00 as I would eventually need about 50 of these units and at $300.00 a piece that adds up to lot of money.
The problem with this I have come to find out is that the UPS battery output on most of the cheaper units is a step wave (square wave) that will not provide enough voltage for the plc to see a 120v input, the battery output will only read 80 to 90 volts on a volt meter even though the spec's on the UPS read 115v +/- 8%.
The UPS that I bought was an APC and after talking with their tech support was told that I would have to buy the more expensive one for about $320.00 to do the job correctly and that is would be larger in physical size which is harder to fit in the panel. I was told by a friend that PK electronic's out of Arizona made one for around $100.00 that would do the job (called the Blackout Buster) but I have now found out they are out of business at least temporarily.
Would anyone have any suggestions for where I could find a UPS that provides true sine wave for around $100.00 as I would eventually need about 50 of these units and at $300.00 a piece that adds up to lot of money.