OVERVIEW
The Powerterm L120C is a combined Power Supply and Battery Charger for small uninterruptible instrument supply applications where 12Volts or 24Volts are required.

Applications include RTUs, dataloggers, remote field instruments and alarm systems where the requirement exists to power 12Volt equipment (such as radios) or 24Volt instruments.

BATTERY MANAGEMENT
During prolonged power outages, the back-up batteries will eventually discharge. If the load remains connected, the batteries can enter their deep discharge phase, which can cause irreparable damage to the batteries, and reduce their capacity and life expectancy.

The PTL120C incorporates a low voltage cut-out that disconnects the loads when  battery voltage falls below its low voltage threshold.

The maximum float voltage necessary to ensure full charge, but not overcharge, is temperature dependent for lead-acid batteries. If the installation is in an environment with widely fluctuating temperature, then fixed voltage chargers will either under-charge or over-charge the batteries.

The PTL120C is provided with external temperature compensation so that the float voltage to the battery is held at its optimum value at all times. Use Model C0003 Temperature probe (supplied separately).

DUAL MODE CHARGING
All sealed lead acid battery manufacturers specify a maximum charging current for the correct life and safe operation of sealed lead acid batteries. This maximum charging current for a battery is based upon the Ampere-hour capacity of the battery. Many conventional switch mode power supplies do not control their maximum delivered current and can cause batteries to be charged from flat with current levels that exceed the manufacturer's recommendation. The PTL120C provides dual-mode charging, with a well defined battery current limit, so that even when the batteries are discharged, the charging current will be controlled.

SYSTEM MONITORING
The PTL120C provides an AC OK contact output. This output can be used to detect power failures without the need for an additional mains detection relay.

BATTERY TESTING
Using the Test Input, the health of the battery can be checked. This function can be included in programmable remote equipment for highest availability of the standby system.