DC UPS battery chargers

The PB251 is a family of 13.8V and 27.6V 220W/275W off line DC uninterruptible power supplies (DC UPS).

When connected the lead-acid batteries these until provide uninterruptible power to the last in the event of mains failure. 110/120V AC Variants are also available.

Feature of the PB251 Family:

• A battery low voltage disconnect switch protects the battery against deep discharge.
• A battery charging current controller limits the battery charging current independently pf the load current to extend the battery life.
• A self-resetting electronic battery circuit breaker protects against nuisance blowing of the battery fuses on accidental load short circuits.
• DC-OK and battery OK alarms including voltage free change over contacts.
• Natural convection cooling, no fan bearings to fail or blocked filters.
• PB 251 Series have very low output ripple and noise which is similar to linear power converters and is suitable for powering radio equipment.
• PB 251 Series is available in chassis mount (CM) and 2RU 19" rack-mounting.
• (RML) Variants.
• PB 251 output power can be increased by attaching a heat sink to the unit (option-H) or by cooling the unit using the external mounting service via a gear plate (option-P).
• PB 256 models with increased output power (PB-256-1210CML and PB-256-2405CML) are available for use where the external mounting surface can act as a heat sink.
• PB 251-12B incorporates Hirose connectors suitable for direct connection to radio base station equipment.
• Designed to comply with safety standard AS/NZS 60950 and RF Emissions standard AS/NZS CISPR11:2002 Group 1, Class B Limits.