Never assume a panel indication is only a nuisance fault
Check for a genuine fire condition first, follow the premises fire procedure, record all indications and use only authorised controls. Any impairment should be managed by the Responsible Person and corrected by a competent fire-alarm engineer.
MOST LIKELY CAUSES
Start with the panel information
Symptom variations Match the exact display, LED and event behaviour. ⌄
- Earth fault LED
- Fault changes with weather
- Fault appears after building work
- Several unrelated circuit faults
- Earth fault clears when a circuit is disconnected
Safe first checks Checks for authorised site staff before engineering work. ⌄
- Check for a red fire indication before treating anything as a fault.
- Read and record the exact display text and LEDs.
- Identify the affected zone, address, circuit, node or power source.
- Check the site log book and recent work.
- Do not disable or reset repeatedly to hide the indication.
Step 1 — Record all associated messages Follow the site fire procedure and use authorised controls only. ⌄
Note whether a particular loop, zone or output is also indicated.
Step 2 — Check recent work and obvious water ingress Follow the site fire procedure and use authorised controls only. ⌄
Do not disturb circuits unless authorised and competent.
Step 3 — Arrange systematic isolation testing Follow the site fire procedure and use authorised controls only. ⌄
The fault should be sectionalised methodically without leaving the building unprotected.
What the indication usually means How this condition develops. ⌄
An earth fault indicates unwanted electrical leakage between a monitored circuit and earth. It can be intermittent and may affect one or several supervised circuits.
Engineer diagnostic sequence Competent-person checks after site information has been captured. ⌄
- Determine positive-to-earth or negative-to-earth leakage where the panel supports it.
- Isolate circuits in a controlled sequence and record each change.
- Measure insulation only using methods safe for connected electronic equipment.
- Inspect external interfaces, damp devices and cable joints.
- Restore and prove every isolated circuit after repair.
Information and equipment needed Useful items for accurate fault finding. ⌄
- Exact panel make and model
- Event log and site log book
- Zone plan and as-fitted drawings
- Cause-and-effect information
- Manufacturer documentation and approved test equipment
Parts that may be involved Components commonly associated with this fault. ⌄
- Field cable
- Detector or module
- Weatherproof enclosure
- Junction box
- Cable gland or insulation repair
When immediate action is required Conditions that should trigger escalation or an impairment plan. ⌄
- The panel is in fire and the cause is not confirmed.
- The control equipment is dead or repeatedly restarting.
- Detection, alarm devices or signalling are disabled or unavailable.
- The fault affects multiple zones, loops, panels or network nodes.
- The panel cannot remain on standby power.
- The site cannot maintain its required fire strategy.
Frequently asked questions Common control-panel questions. ⌄
Can the internal buzzer be silenced?
Authorised users can normally acknowledge or silence the internal panel buzzer after reading and recording the condition. The fault remains active until its cause is repaired.
Should the panel be reset?
Only after the initiating condition has been investigated and cleared. Repeated resetting can remove useful information and delay repair.
Who should repair the fault?
A competent fire-alarm engineer familiar with the equipment, system design and site fire strategy.