Caroline County, Virginia Request for Proposals Project 25 Radio ...

UHF/700 MHz P25 Radio Communications SystemRequestion for ProposalsCaroline County, Virginia1. 10 kVA output2. Single phase3. 60 Hz4. 0.8 Power Factor5. Minimum one hour run timeD. Operational Requirements:1. Automatic operation includes the following:a. Normal Conditions – Load is supplied with power flowing from thenormal power input terminals, through the rectifier-charger andinverter, with the battery connected in parallel with the rectifierchargeroutput.b. Abnormal Supply Conditions – If normal supply deviates fromspecified and adjustable voltage, voltage waveform, or frequencylimits, the battery supplies energy to maintain constant, regulatedinverter power output to the load without switching or disturbance.c. If normal power fails, energy supplied by the battery through theinverter continues supply-regulated power to the load withoutswitching or disturbance.d. When power is restored at the normal supply terminals of thesystem, controls automatically synchronize the inverter with theexternal source before transferring the load. The rectifier-chargerthen supplies power to the load through the inverter andsimultaneously recharges the battery.e. If the battery becomes discharged and normal supply is available,the rectifier-charger charges the battery. On reaching full charge,the rectifier-charger automatically shifts to float-charge mode.f. If any element of the UPS system fails and power is available at thenormal supply terminals of the system, the static bypass transferswitch switches the load to the normal AC supply circuit withoutdisturbance or interruption.g. If a fault occurs in the system supplied by the UPS, and currentflows in excess of the overload rating of the UPS system, the staticbypass transfer switch operates to bypass the fault current to thenormal AC supply circuit for fault clearing.May 27, 2011 Page 66 of 134