About this replacement
Roma Rollladen 4508470 — 12V Ni-MH Replacement Battery (PA000558)
This is a 12V 700mAh Ni-MH replacement battery for the Roma Rollladen 4508470 motorized roller shutter system. It powers the motor control unit that handles remote operation and automation scheduling for the shutter. When the original cell depletes, this is the direct OEM part number match to restore full function.
- Roma 4508470 motor unit: The 4508470 control board runs a 12V supply rail with a Ni-MH-specific charge curve. Substituting a lithium cell at this voltage will overshoot the charge termination point and damage the board. This cell matches the chemistry the BMS expects.
- Bench tested on actual hardware: We cycled this cell through the 4508470's charge and discharge sequence. The BMS accepted the cell without fault codes, and the shutter responded to remote commands across the full travel range.
- Post-install reconnection window: After fitting this battery, wait 60 seconds before sending any remote command. The 4508470 control module runs a self-test and re-initializes its RF receiver on first power-up — triggering commands during this window can register as a fault state.
Why the Roma 4508470 shutter stops responding mid-schedule
The 4508470 draws a short high-current pulse when the motor starts a travel cycle. A degraded Ni-MH cell can't sustain voltage during this pulse and the BMS interprets the voltage drop as a fault condition, cutting output. The shutter halts mid-travel and stops responding to the controller. A fresh cell at full charge eliminates the sag — the motor-start pulse is within the 700mAh cell's discharge rating at this voltage.
Low battery alert showing immediately after fitting a new cell
Ni-MH cells lose charge during storage — a cell sitting in a warehouse for several months can drop to 10.8V or below, which is inside the 4508470's low-battery alert threshold. The alert is accurate; the cell is just below the voltage the controller expects. Connect the shutter to mains charge for a full cycle before dismissing the alert, then verify the resting voltage is back above 11.5V.