4.8V 600mAh Nickel-Cadmium Emergency Light Battery - Parallel Configuration

This 4.8V 600mAh nickel-cadmium battery is a replacement power pack for Duceri EM2WMEXSIGN emergency lighting units and compatible emergency sign fittings. The battery uses a parallel cell configuration with four sub-C NiCd cells connected to deliver 600mAh capacity at 4.8V nominal voltage, pre-wired with a two-pin connector that matches the standard Duceri emergency lighting socket.

Emergency lighting batteries like this sit on permanent trickle charge within the emergency fitting, maintaining full capacity until mains power is lost. At that point the battery discharges to power the emergency LED or lamp for the required duration (typically 3 hours for most UK commercial installations). Over time, NiCd cells lose charge capacity through repeated cycles, and regulations require periodic replacement to maintain compliance with BS 5266 and BS EN 60598 standards.

The parallel configuration means all four cells discharge simultaneously to meet the current draw of the emergency light, rather than in series which would increase voltage. This specific topology matches the voltage requirement of Duceri EM2WMEXSIGN units and avoids over-voltage damage to the LED driver circuit. The battery pack measures approximately 90mm x 45mm x 20mm (cell pack only, excluding lead length) and weighs 70g, fitting within the compact housing of standard emergency exit signs and bulkhead fittings.

Nickel-cadmium chemistry tolerates frequent shallow charge-discharge cycles better than older lead-acid emergency batteries, and operates across a wider temperature range (typically -20°C to +50°C). The cells are shrink-wrapped together and pre-assembled with red and black polarity leads terminating in a white connector block. Installation involves isolating the mains supply, disconnecting the old battery pack, and plugging in the replacement — no soldering or terminal crimping required.

Product Specification Sheet

How often should emergency lighting batteries be replaced?

BS 5266 recommends replacement every 4 years under normal operating conditions, or sooner if monthly and annual discharge testing reveals reduced capacity. Commercial premises must log replacement dates in their emergency lighting maintenance records.

Is this battery compatible with other emergency light brands?

This battery is designed for Duceri EM2WMEXSIGN emergency fittings. Compatibility with other brands depends on matching the voltage (4.8V), capacity (600mAh minimum), cell configuration (parallel), and connector type. Check your existing battery specifications before ordering a replacement.

Can I install this battery myself?

Installation involves isolating the mains supply at the consumer unit, opening the emergency fitting, disconnecting the old battery connector, and plugging in the new pack. In commercial premises this work must be carried out by a competent person and logged in the building's maintenance records. Domestic DIY installation is possible if you are confident working with mains isolation.

What is the difference between parallel and series NiCd packs?

Parallel configuration connects cells positive-to-positive and negative-to-negative, maintaining the voltage of a single cell (1.2V per cell, 4.8V total for four cells) while adding the capacity of each cell together. Series configuration connects cells end-to-end, adding voltage but keeping the same capacity. Emergency lights specify which configuration they require — using the wrong type can damage the LED driver or fail to provide the correct run-time.