Is Your UPS Killing Your Lab Instrument? April 12 2017, 0 Comments
When cheap UPS systems intended for home computers are purchased and used with lab instruments or sensitive electronics, the results can be disastrous. As outlined in the letter at the end of this page, the UPS and/or the attached instrument can fail catastrophically if the wrong type or capacity UPS is used.
Battery Backup Power, Inc. keeps up with product bulletins, tech notes, white papers, and general compatibility for all major lab instrument manufacturers. Recently, we were asked why we recommend larger capacity UPS systems for certain instruments when compared to other UPS companies as well as why our systems are more expensive on average.
The answer has multiple parts.
1. Certain electronic devices create non-linear or varying loads that can fatigue a transformer sized 1:1 or even 2:1 with the maximum load. A larger capacity UPS will be able to better handle these variations and prolong the life of the UPS and its attached devices. This is sometimes referred to as derating and/or over-sizing the UPS and/or transformer to ensure compatibility, longevity, and performance.
2. Rapid variations in the load (as seen in many lab instruments) can build up heat in the transformer which needs to be dissipated. Battery Backup Power, Inc. UPS systems have one or many (depending on the model) active ball bearing fans that consistently run to ensure heat build up is quickly dealt with. Due to the high performance of the fan(s) and internal cooling systems, our UPS systems can be noisier than comparable units.
3. Our larger 6 kVA to 20 kVA single phase UPS systems have internal transformers with an approximate K Factor of 4. K Factor rated transformers have larger air gaps built in to help dissipate heat build up (referred to as harmonics). K Factor transformers are more expensive than standard transformers.
4. We DO NOT use ferroresonant transformers in our UPS systems like some other UPS manufacturers do (see below Agilent letter in regards to UPS/instrument compatibility).
5. Our company policy is to decline to sell or cancel any order for a UPS that does not meet our recommended minimum capacity safety margin for any electronic device with known capacity and/or operating requirements.
Below is an example letter from an instrument manufacturer describing some of the compatibility issues created when pairing an instrument to the wrong type of UPS, power conditioner, isolation device, or transformer.