Chromatography Forum

Our company is in south of Florida. We often lose power suddenly in a couple of seconds which shock HPLC dead.
Does anybody know what kind Battery would I use to be back up power? Thanks.
Jady

Go to an office supply store and get a "UPS" (uninterruptible power supply) designed for computers. Check the specifications on your chromatograph to establish how much current it draws and get a UPS that exceeds that capacity.

I can tell you, UPS from an office supply store will not be large enough. You also have to take into account everything drawing and a amperimetric detector pulls a large amount of power. I am currently going through the same situation with an LC and a GC - I asked the manufacturer what they recommend. I would ask Dionex and I realize the size they will suggest might be overkill but better safe than sorry.

I will 2nd what 'Phycal' states, do NOT go to an office supply store and buy one of their cheap UPS systems. Most of these are junk and can hurt your computer over time. Three things to keep in mind:

(1) When selecting an Uninterruptible Power Supply (UPS) for your analytical instruments, only purchase one which outputs a true sinewave voltage (just like real AC power). Most of the UPS systems sold at the local office and electronic supply stores output either square wave A/C or pseudo-sine wave (which is not the real thing). Some brands will tell you they offer true sinewave outputs right in the model number or package, but always double-check the specifications (e.g. APC's "Smart-UPS" offer sinewave outputs, but NOT the Smart-UPS SC models.). Using a supply that outputs something other than true sinewave power can damage the power supply of what it is attached to leading to premature failure of system you are trying to protect.

(2) Calculate the maximum load of the system being protected in Volt amps (VA) and purchase a system that can provide power well above that load for the time period you want to protect. *I think 20 or 30 minutes of run time, at load, is a realistic guideline to go by. A 700 VA UPS will usually power most desktop computers and a monitor for that amount of time. Most brownouts last for just seconds, but that is enough time to shut everything down or loose communication. If a power outage is more than five minutes in length, then it may be a while before it is restored. In this case, be sure to safely shut everything down manually before you run out of battery reserve power. Once everything has been turned off, remember to turn OFF the UPS system to stop it from slowly draining the battery (most computers are still turned ON and using power when they are OFF). Doing so will preserve the remaining battery capacity. Just turn the UPS back on when power has been restored.

(3) Unless you want to spend really BIG dollars, just put a high quality UPS system on the computer. A high quality UPS system designed for a single high current draw instrument will cost thousands of dollars. Use a dedicated, high quality power conditioner and surge suppressor on the analytical instrument circuits ($85 and up each, not the $20 models sold at most box stores). The computer system is really what you want to protect first. If the computer gets knocked out you loose communication to the analytical system. This usually means it will continue to run on and on without stopping. If the computer is protected by a UPS and the power gets glitched (seconds) or goes out, then the computer may sense this and abort the run or shut the system down (if it has not been shut down). This is the type of approach we have used in our labs for twenty years and it works great during brown outs and black outs. The computers stay on long enough to properly and safely shut down everything without loosing data (which is the key). The instruments are all connected to individual power conditioners/surge suppressors (most made by Tripp lite) so are protected from brown outs and surges. To protect our equipment from large surges, we also install a high amperage DELTA lightning arrestor (100,000 AMP, 3000 joules per pole, unlimited number of surge capacity) on the panel and individual Delta surge capacitors on each critical 20A circuit that supplies power to laboratory equipment. These extras steps provide protection from direct lightning strikes and surges to the panel and equipment.

Both Phycal and HPLCCONSULT offer good recommendations. Dionex has a number of customers who install UPS units and power conditioners, especially in mission critical sites and thunderstorm-prone regions such as yours.

Please contact me directly from this post (profile) and the recommended specifications/approved vendor can be provided for your ICS-3000 system. You may also contact your Regional Dionex Service Manager for assistance.