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Hugh Speirs · Apr 2026
Fault guide · GivEnergy EPS / backup
GivEnergy EPS Not Working During a Power Cut
You have a GivEnergy battery but the house went dark during a grid outage. EPS (Emergency Power Supply) is disabled by default on all GivEnergy inverters and requires both a software setting and a dedicated wired circuit. This guide covers every reason EPS may have failed — and how to set it up correctly. For the general technical background, see how backup power works.
Free remote diagnostic pay only if we fix it — from £95 if remediable remotely
- EPS disabled by default — must be enabled in portal
- Requires dedicated wired circuit — not whole house
- SoC, overload, and wiring causes covered
EPS configuration is model-specific
EPS setup on GivEnergy varies between Gen 1, Gen 2, Gen 3, and All-in-One models. Whether your system has a wired EPS circuit, what the SoC minimum should be set to, and which portal settings apply — we can review and configure this remotely.
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Excellent response to diagnose a problem on our SolarEdge installation. Kept us informed at every step. Diagnosis quickly completed and solution implemented.
Les Bennett · May 2026
Ronald was able to organise a brilliant electrician with extensive experience of GivEnergy systems local to me in the SW. I have now got a fully functioning system and suspect that my electricity bill will be substantially reduced or in credit over a year. Also when said electrician discovered an overvoltage in the my local grid, Ronald prepared a very lucid and comprehensive report of the situation which I have now supplied to my local grid. Cannot recommend Ron and Dan enough.
Ian Macmillan · Jul 2026 Google
Just had my whole givenergy system go down. Battery and inverter. Ron sorted me out today 3 hours to get it all sorted. Clear instructions and successful. Could not ask for better. Now that givenergy has gone bust i was concerned as to where to go for help. I have found it and can recommend them to all you givenergy users out there. Off for a cup of coffee now😄
Eaton Edwards · Jul 2026 Google
Contacted Ron with a problem and he sorted it out quickly with no problems at all. Very knowledgeable on anything solar/ batteries. I would recommend him to anyone
Phill · May 2026
My 90-year-old father-in-law had a solar system installed nearly three years ago that never worked properly and kept tripping out. Neither the original installer nor GivEnergy could resolve the issues, and we were even pushed towards replacing the system entirely when GivEnergy went bust. I contacted Ron at Solar Tech Support via WhatsApp, and within a few hours he had diagnosed multiple faults — including incorrect wiring that posed a potential fire risk. He carried out a home visit in Nottingham for £295 (including parts), fixed everything, completed firmware updates, and ensured the system was fully operational. Since then, it has worked perfectly. Ron was knowledgeable, responsive, and took the time to explain everything clearly. Highly recommended — excellent value and complete peace of mind.
Julian F · Jun 2026 Google
Understanding EPS
What GivEnergy EPS actually does — and what it doesn't
EPS (Emergency Power Supply) is GivEnergy's battery backup function. Understanding exactly how it works is essential before diagnosing why it failed.
WHAT EPS DOES
Powers a dedicated backup circuit
When the grid fails, GivEnergy's EPS mode switches the dedicated EPS output terminals from grid power to battery power within approximately 20ms. Only circuits wired to those specific terminals receive backup power.
WHAT EPS DOESN'T DO
Does not back up the whole house
The main consumer unit and all sockets and lights not wired to the EPS circuit remain off during a grid outage. EPS is for essential circuits only — typically a few key sockets, boiler, or lights selected at installation.
WHAT EPS NEEDS
Both wiring and settings
EPS requires: (1) a dedicated EPS output circuit physically wired by the installer to the inverter's backup terminals, AND (2) EPS mode enabled in the GivEnergy portal. Missing either one means no backup power.
Not all GivEnergy installations include EPS wiring. Many UK installers do not wire the EPS output circuit as standard — it is an optional additional cost. If you were not told at installation that EPS backup was included, your system may not have a wired EPS circuit at all. This is the most important thing to establish before adjusting any settings.
Cause 1 — most common
Most common
EPS mode is not enabled in the portal
EPS is disabled by default on every GivEnergy inverter. It must be explicitly enabled in the GivEnergy portal. This is the most common reason backup power doesn't work — the physical wiring is correct but the inverter has never been told to use it.
How to check if EPS is enabled
1
Log into the GivEnergy portal
Go to givenergy.cloud → My Inverter → System Mode Settings.
2
Look for the EPS / backup power setting
EPS settings are typically found in the System Mode Settings or Advanced Settings section depending on your portal version. Look for a toggle or option labelled EPS, Emergency Power Supply, or Backup. If it is set to Off or Disabled, this is your problem.
Note: The exact location of the EPS setting varies between portal versions and inverter generations. On some models it is under Battery Options rather than System Mode Settings. If you cannot find it, see the how to enable EPS section below, or book a remote session for model-specific guidance.
3
Check if EPS was reset by a firmware update
GivEnergy firmware updates can reset settings including EPS mode back to defaults. If EPS was working and then stopped after an update, check whether the setting has reverted to disabled.
Cause 2 — very common
Wiring — requires engineer
No dedicated EPS output circuit was installed
Even if EPS mode is enabled in the portal, backup power only reaches circuits that are physically wired to the inverter's EPS output terminals. Many UK GivEnergy installations do not include this wiring — it is an optional additional cost that many installers don't include as standard.
How to tell if you have an EPS circuit
→Check your original installation quote or contract — does it mention EPS wiring, backup circuit, or emergency supply as a line item?
→Look at your consumer unit — is there a separate MCB or circuit labelled EPS, Backup, or Emergency?
→Check the inverter itself — are there cables connected to the backup/EPS output terminals? (Visual check of the terminal block labels only — do not open the inverter)
→Ask your original installer whether EPS output wiring was included in the installation
Adding an EPS circuit — what's involved
Adding an EPS circuit is an electrical installation job. A qualified electrician or GivEnergy-experienced engineer runs a dedicated circuit from the inverter's EPS output terminals to a sub-board or specific sockets and circuits that you want backed up.
You need to decide which loads to back up — common choices are a key socket, the boiler, fridge, and critical lighting. The total load must not exceed the inverter's EPS output rating (typically 3kW on Gen 2, 6kW on Gen 3 and AIO).
This is a notifiable electrical installation and should be done by a Part P registered electrician or a qualified solar engineer.
Do not attempt EPS wiring yourself. The inverter's EPS output terminals are live electrical connections. This wiring must be done by a qualified engineer. Incorrect wiring could backfeed mains voltage onto a circuit assumed to be dead during an outage — a serious safety risk for engineers working on the grid.
Cause 3
Battery SoC
Battery was below the minimum SoC reserve at the time of the outage
GivEnergy EPS will not activate if the battery state of charge is at or below the EPS reserve threshold. If the outage happened at night after a long discharge period, or the battery has been undercharging due to a separate fault, EPS may have had nothing to draw from.
Check battery SoC at time of outage
In the GivEnergy portal, navigate to the battery SoC graph and look at what the SoC reading was at the time the outage occurred. If the battery was at or near the reserve minimum (or at 0%), EPS had insufficient charge to operate.
The EPS reserve setting is typically in Battery Options under the minimum SoC or reserve percentage. Check what this is set to — if the battery was above this at the time of the outage but EPS still didn't work, the SoC is not the cause.
Configuring the EPS reserve correctly
The EPS reserve (minimum SoC) determines how much battery charge is held back specifically for backup power. Setting it too low means EPS may be unavailable when you need it. Setting it too high means less battery capacity for daily use.
→A 20% reserve provides approximately 1–2 hours of moderate EPS load on a 5kWh battery
→Set the reserve based on how long you want backup capability — not so high it impacts daily operation
→Consider keeping Timed Charge active overnight so the battery enters each night with a full charge ahead of potential outages
Cause 4
Overload
EPS tripped immediately — load exceeded inverter backup rating
EPS activated but then cut out within seconds. The total power draw on the EPS circuit exceeded the inverter's backup power rating, triggering the overload protection. This produces the fault code STORAGE_ERROR_BACKUP_OVERLOAD_FAULT.
GivEnergy EPS power ratings
Approximate EPS output ratings
Gen 1 hybrid (3.6/5.0 kW)2.6kW
Gen 2 hybrid~3kW
Gen 3 hybrid (3.6/5.0 kW)6kW
Gen 3 hybrid (8.0/10.0 kW)8–10kW
All-in-One6kW
Ratings vary by inverter model. Always verify against your specific model's datasheet before sizing an EPS circuit.
What to do about an overload
STORAGE_ERROR_BACKUP_OVERLOAD_FAULTCheck the portal event log for this code — if present, the load on the EPS circuit exceeded the inverter's backup power rating.Review what loads are wired to the EPS circuit — add up their total wattage at startup (startup draw is often higher than running draw).
Remove high-draw appliances from the EPS circuit — electric showers, kettles, and electric ovens are not suitable EPS loads.
Any EPS circuit wiring changes require a qualified engineer.
Suitable and unsuitable EPS loads
Suitable EPS loads
✓Gas boiler (control board only, typically 100–200W)
✓Fridge / freezer (100–200W running, brief higher startup)
✓LED lighting (10–20W per circuit)
✓Phone/device chargers (20–100W)
✓Router and broadband equipment (10–30W)
✓Low-draw medical equipment (always check with manufacturer)
Unsuitable EPS loads
✗Electric shower (7–10kW — far exceeds any EPS rating)
✗Electric cooker or hob (3–12kW)
✗Kettle (2–3kW — brief but trips overload)
✗Tumble dryer (2–3kW)
✗Immersion heater (2–3kW)
✗Air conditioning units (1–5kW with high startup draw)
Total load on the EPS circuit must not exceed the inverter backup rating. Account for startup surges — motor-driven loads like fridges draw 2–3× their running wattage for 1–2 seconds on startup.
Configuration
How to enable EPS
Enabling and configuring GivEnergy EPS correctly
Before enabling EPS in the portal, confirm that a dedicated EPS output circuit was physically wired at installation. Enabling EPS without the correct wiring has no effect — it will not provide backup power and may cause unexpected behaviour.
EPS setup checklist
1
Confirm EPS wiring exists
Verify with your installer documentation or by visually checking the consumer unit for a dedicated EPS/backup circuit. If not installed, contact a qualified engineer to add one before proceeding.
2
Enable EPS in the GivEnergy portal
Go to givenergy.cloud → My Inverter → System Mode Settings. Find the EPS or backup power setting and enable it. Press Submit to apply. The exact label and location varies between portal versions — it may be under Battery Options or Advanced Settings on some models.
Remote configuration: EPS settings can be updated remotely via the portal. No site visit is needed just to enable or reconfigure the EPS setting — only if wiring changes are required.
3
Set the EPS reserve (minimum SoC)
Under Battery Options, set the minimum SoC reserve to the level that gives you your desired backup duration. A 20–30% reserve is a reasonable starting point for most households. This is the charge held back exclusively for EPS use.
4
Test EPS — safely
To test EPS without a real power cut, you can turn off the main AC isolator below the inverter while the battery is charged and EPS is enabled. The EPS circuit should remain powered from the battery. Only do this if you understand what you are doing — turning off the AC isolator isolates the inverter from the grid. Restore it promptly. Do not turn off the consumer unit main switch as this may disconnect EPS loads.
Safety: EPS testing involves working near live electrical equipment. If you are not comfortable doing this, a qualified engineer can test EPS as part of a site visit or we can assist with remote configuration verification.
Also check
Appliance compatibility with EPS
Some appliances are sensitive to the ~20ms switching time when EPS activates. Computers, NAS devices, and some boiler controls may restart during the brief switchover even when EPS is working correctly. This is not an EPS fault — it's a limitation of the technology. A UPS (uninterruptible power supply) on sensitive equipment can bridge this gap.
Also check
EPS and the inverter status light
During EPS operation, the inverter status light behaviour changes — the inverter is no longer connected to the grid and operates in island mode. This is normal. If the battery depletes fully during EPS and the grid is still down, all power will be cut. The inverter will restart automatically when grid power returns.
Related GivEnergy pages
Battery not charging
Battery not charging overnight — low SoC means less EPS reserve too.
Red light / battery alarm
Battery fault codes including EPS overload and protection events.
Firmware issues
Firmware updates that reset EPS mode or other system settings.
All GivEnergy problems
Browse all GivEnergy fault guides — battery, portal, CAN, firmware and more.
This is a brand-specific version of our general no backup during power cut guide, which covers all brands.
GivEnergy EPS questions
No. GivEnergy EPS only powers circuits physically wired to the inverter's dedicated EPS output terminals. Your main consumer unit and all sockets and lights not on the EPS circuit will remain off. EPS is designed for essential loads only — a few key circuits selected at installation time. If you want whole-house backup, that requires a different system architecture.
Duration depends on the battery capacity, the SoC at the start of the outage, the EPS reserve setting, and the load on the backup circuit. As a rough guide: a 5kWh battery at 80% charge running a 200W load would last approximately 20 hours. Running a 1kW load (fridge + a few lights + boiler) would last around 4 hours from that starting point. Reduce load to extend duration.
Yes, in most cases. A GivEnergy-experienced electrician can add the EPS output circuit retrospectively. The inverter already has the backup terminals — it's a matter of wiring the correct circuits to them and enabling EPS in the portal. This is a notifiable electrical installation and must be done by a qualified Part P registered electrician.
Two possible causes: the boiler isn't wired to the EPS circuit (it's on a standard circuit that goes off during an outage), or the boiler control system is sensitive to the ~20ms EPS switching delay and resets. Some boiler controls need to complete a power-on sequence and won't do so correctly after a brief interruption. A small UPS on the boiler can bridge this gap if the ~20ms delay is the issue.
Yes. EPS draws from the battery regardless of whether solar panels are generating. During a night-time power cut, EPS will run entirely from stored battery charge. If the grid outage extends into daylight and your system has panels, solar will also charge the battery and extend EPS duration — but only if the panels can generate (clear skies, inverter running in island mode).
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