EMMIS isolation transformers in UPS applications
The proper selection and installation of transformers in UPS applications is an important decision which can benefit the functionality, efficiency and safety of the installation.
Specifically, the use of certified isolation transformers in UPS applications ensures the following:
- The supply voltage is adjusted to the required levels. This happens when the UPS power supply voltage is different from 3x400V (input) or if the load that is supplied, operates at a different voltage than that of the UPS output.
- The uninterrupted and safe equipment protection against neutral loss. The UPS operation requires a neutral wire in its supply. The transformer generates neutral when it does not exist from the source. In cases where the source has a neutral wire, the installation of an isolation transformer ensures the proper UPS functioning and the supply of the load, in case of loss of neutral from the installation.
- Load operation is being normalized as far as the harmonics are concerned. When the transformer is placed at UPS input, it filters out the harmonics generated by the UPS to the installation. When the transformer is positioned in the UPS output, it filters out the harmonics that the UPS receives from the load.
- Maximum safety. Maximum safety is achieved due to the galvanic isolation of the transformer both in input and output. For maximum safety, is necessary the selection and installation of a certified transformer according to international standards EN/IEC 61558-2-4, EN/IEC 61558-2-6 and EN/IEC 61558-2-15.
- Energy losses are mnimized. Technologically advanced UPS have a very high power factor which is further burdened by the transformer. For this reason, the isolation transformer should have the minimum possible energy losses. This is secured only with the installation of a certified transformer.
The selection and installation of certified transformers in UPS installations ensures maximum benefits in all above cases.