Transcript
FAQ: PA-2 and PA-4 Power Adaptors •
Can Power Adapters be used on non-standard devices on the airfield?
Question: I noted in your literature that the power adapter is not guaranteed to work with other manufacturers’ equipment. Can the application described below work, or are there other factors we are not aware of that would prevent the circuit from operating the motor adequately? We have an airfield with a communications manhole that the client wanted lighting in, and therefore, we need to put a sump pump in to keep water out. As the manhole is a considerable distance from the vault, they would like to run the sump pump off the existing 6.6A airfield lighting circuit. It is a ½ HP sump pump, operating at 120V AC. In the manhole, there is an ADB power adaptor PA-4 with a capacity of 2995VA. It appears it could handle the 1035VA motor load. Answer: The application of unknown loads with our power adapters is problematic. The PA-4 is a resonating circuit that goes into saturation at a low input current (2.8A). It goes into saturation in order to output a regulated AC voltage. Because it saturates at a low current and stays saturated up to an input current of 6.6A, it has a low input Power Factor. So the load imposed on the CCR by a PA-4 is 2995VA. However, the maximum load that can be placed on the secondary of the PA-4 is only 670VA. Therefore, for this application, it cannot handle the sump pump’s 1035VA motor load. Note that for the PA-2, the maximum secondary load is 150VA. Another problem with non-standard airfield devices is the possible interaction of the load with the power adapter. Certain kinds of loads interact with the power adapter’s electrical resonating components causing the power adapter to be thrown out of resonance. This may cause the output voltage to vary from ~80V AC to over ~300V AC. Therefore, we never recommend using the power adapter unless it is with a known load that we have already tested. The only products we have definite knowledge about are our REILs using xenon flash lamps and wind cones. Even on ADB Airfield Solutions’ xenon REILs, we convert all AC coils (such as relays) to a type that operates on DC. A DC load has shown to have very little effect on power adapter operation. If you really want to try a power adapter with non-standard devices such as sump pumps, drills, compressors, remote 120V AC receptacles, motors, fluorescent lights, etc., we recommend that you buy one and try it out on the exact circuit it will be installed in. This is important because different types of CCRs produce different wave shapes, which can also affect the operation of the power adapter. ADB Airfield Solutions cannot guarantee operation of any power adapter except for known loads that we have previously run tests on.
ADB Airfield Solutions P.O. Box 30829 I 977 Gahanna Parkway I Columbus, OH 43230 I Tel: 614.861.1304 I Fax: 614.846.2069 I adb-air.com
