Telecom cabinet: should you use the PM-LV48100 telecom battery or a standard rack battery?

Direct answer: On the published specifications the two 48V 100Ah modules are electrically the same: 48V, 100Ah, 4.8 kWh, 54.75V maximum charge, 37.5V cut-off and 100A continuous, in the same 3U size. The visible difference is that the telecom page lists SNMP alongside RS485, RS232 and CAN-bus. Choose the telecom version if your site monitoring uses SNMP, then confirm the rectifier settings, temperature range and site standards with the operator.

Page figures. PM-LV48100-TELECOM and PM-LV48100-3U both list 420 × 440 × 136 mm, 39 kg, IP21, charge 0°C to 60°C and discharge -20°C to 60°C. The PM-LV48150-TELECOM is a 4U, 7.2 kWh, 54 kg option with the same voltage window and 100A continuous rating.

Monitoring. Telecom sites usually report alarms to a network management system. If yours uses SNMP, a battery that offers it may save a protocol converter; ask Redway which data points and alarms are exposed and which network interface is used. If the site controller reads batteries over RS485 or CAN, check that its protocol is supported.

Voltage and the rectifier. Many telecom DC plants run at a nominal 48V, often as -48V with the positive bus grounded. The battery’s 37.5V–54.75V window must suit the rectifier’s float and boost settings and the load’s low-voltage disconnect. Agree the charge voltage, current limit and any float setting with Redway before connecting, and confirm the site’s grounding scheme with the operator.

Backup time. Estimate it from energy and load: a 4.8 kWh module feeding a 1.2 kW load gives at most about four hours before losses and reserve, and you should keep a margin for ageing and low temperature. Paralleled modules add energy, and the pages list up to 64 in parallel; check the site’s breaker and cable ratings for the combined current.

Temperature. Outdoor cabinets can exceed or fall below the charge range. IP21 modules need a sealed, conditioned or heated cabinet; the pages list self-heating as an option. Our post on backup time for a small server room shows the same runtime method for indoor IT loads.

Documents to request. For a telecom rollout, ask for the datasheet, manual, UN 38.3 test summary and any listings the operator requires, plus the SNMP data map if you will use it. Our post on documents to request with an order has a fuller list.