Battery and power faults can reduce or remove the system’s standby capability
Keep the dedicated mains supply available where safe, avoid repeated discharge tests and escalate promptly if batteries are hot, swollen, leaking or the panel cannot remain operational on standby.
MOST LIKELY CAUSES
Start with the power and battery information
Symptom variations Match the exact battery, charger and PSU behaviour. ⌄
- White or green deposits
- Terminal discolouration
- Loose connector
- Battery warm or swollen
- Intermittent battery fault
Safe first checks Checks for authorised site staff before engineering work. ⌄
- Record the exact battery, charger or PSU message.
- Check whether the mains indicator is normal.
- Look for swelling, heat, leakage or loose external leads.
- Check whether a recent mains failure occurred.
- Do not intentionally discharge the system while a battery or charger fault is active.
Step 1 — Do not disturb a leaking or hot battery Follow the site fire procedure and avoid unnecessary battery discharge while power faults are active. ⌄
Isolate the area and arrange safe replacement.
Step 2 — Record the condition Follow the site fire procedure and avoid unnecessary battery discharge while power faults are active. ⌄
Photograph the terminals and note any swelling, odour or leakage.
Step 3 — Use competent maintenance procedures Follow the site fire procedure and avoid unnecessary battery discharge while power faults are active. ⌄
Cleaning and replacement should be completed with the correct PPE and safe isolation.
What the indication usually means How this battery or power condition develops. ⌄
Battery terminal corrosion may be caused by leakage, loose connections, heat, contamination or long-term chemical reaction around the terminals.
Engineer diagnostic sequence Competent-person checks after the site information has been captured. ⌄
- Disconnect under the manufacturer's safe procedure.
- Assess whether the battery has leaked or vented.
- Clean or replace affected leads and terminals.
- Check resistance and temperature at the connection.
- Inspect the enclosure and PSU for chemical damage.
Information and equipment needed Useful items for accurate fault finding. ⌄
- Panel and PSU make and model
- Required standby and alarm duty
- Battery capacity, age and installation date
- Manufacturer-approved meter and battery test equipment
- System log book and recent mains-failure history
Parts that may be involved Components commonly associated with this fault. ⌄
- Matched battery set
- Battery leads
- Terminal hardware
- Approved cleaning materials
- Protective equipment
When immediate action is required Conditions that should trigger escalation or an impairment plan. ⌄
- The panel cannot remain operational on standby.
- Batteries are hot, swollen, leaking or producing an unusual smell.
- The charger or PSU fault affects alarm outputs, signalling or interfaces.
- The battery fuse repeatedly operates.
- The system has experienced a prolonged mains failure.
- The required standby duration cannot be demonstrated.
Frequently asked questions Common battery and power questions. ⌄
Is battery voltage alone enough to prove condition?
No. A battery can show an acceptable open-circuit voltage but still have poor capacity or high internal resistance.
Should only one battery in a series pair be replaced?
Normally no. Batteries in the same series set should be replaced together with matched type, capacity and age.
Can corroded terminals simply be cleaned?
Only after checking for leakage, heat and battery deterioration. Damaged leads or leaking batteries should be replaced.