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SCADA

SCADA gives operators real-time visibility, control, and diagnostic capability across their electrical and power generation infrastructure — from a single unified platform.

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Generators

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  • New Generators

    New diesel generators from leading manufacturers, supplied to suit any application from standby to prime power.

  • Used Generators

    Used diesel generators, refurbished and load bank tested in-house before sale.

Containerised Generators

Our containerised solutions combine generator, fuel system, controls, and switchgear in a purpose-built enclosure.

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G99 Panels & Testing

G99 Testing
G99 Testing

Overview

G99 governs how generators connect to the UK distribution network. Compliance is a legal requirement enforced by Distribution Network Operators.

We test existing mains protection relays against current G99 requirements, and supply and install new compliant relays where needed.

All work is delivered by NIE Networks approved engineers, with full test certification provided for direct submission to the DNO.

Benefits

DNO Compliance

Meet current G99 requirements and the connection standards required by NIE Networks across Northern Ireland.

NIE-Approved Engineers

Testing carried out by engineers on NIE Networks’ approved supplier list — no DNO attendance required.

Test & Install in One Visit

Where existing relays fail, we supply and install compliant replacements within the same site visit.

Certified Documentation

Full test certificates issued, ready for direct submission to the Distribution Network Operator.

Faster Project Delivery

Combined testing, supply, and installation removes handoffs and shortens the path to DNO approval.

Trusted Equipment

New relays supplied from leading manufacturers including ComAp InteliPro and Deep Sea Electronics P100.

Features

 

  • Testing of existing mains protection relays against current G99 requirements
  • Supply and installation of new G99-compliant relays
  • NIE Networks approved supplier — self-witnessed testing without DNO attendance
  • Equipment supplied from leading manufacturers including ComAp InteliPro and Deep Sea Electronics P100
  • Full test certification provided, ready for submission to the Distribution Network Operator
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Get in Touch

Need to confirm whether your existing mains protection relays meet current G99 requirements? Or planning a new generator installation that requires DNO-compliant protection from the outset?

Get in touch to arrange G99 testing — we’ll attend site, carry out the tests, and where necessary supply and install compliant replacements. Test certificates are provided ready for direct submission to NIE Networks.

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Why Choose Us

As approved suppliers on NIE Networks’ tendered list, our engineers can carry out G99 witness testing without the need for DNO attendance — saving you time, cost, and the scheduling delays that often come with DNO visits. Test certificates are issued ready for direct submission, with no follow-up required.

That same approval, combined with our in-house electrical engineering capability, means we can also identify, supply, and install replacement relays in a single visit if existing equipment falls short — minimising the disruption and downtime that typically accompanies G99 non-compliance findings.

Case Studies

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Mater Hospital, Belfast
Control Systems
Mater Hospital, Belfast

AC Automation designed, supplied, and commissioned a Power Management Control System for Belfast Health and Social Care Trust’s Mater Hospital site, delivering a fully integrated platform for managing multiple electrical assets through a single coordinated architecture. Built on ComAp controllers, the system coordinates two transformer incomers, two synchronising generators, a 2 MW battery energy storage […]

Installation & Commissioning
Control Systems
Royal Victoria Hospital, Belfast
Generator Hire
UEFA Super Cup Final, Belfast
Installation & Commissioning
Control Systems
G99 Testing
UK Government, Scotland

Our reviews

Hear first-hand from our incredible community of customers.

AC Automation has been a long-standing contract partner to NI Water for over 10 years.  Providing goods and services 24/7, which includes planned and remedial maintenance.  They provide generator hire and have provided support during major incidents.Their work helps keep our generator fleet available and well maintained, supporting the delivery of services to our customers.
Kieran HarkinSenior Contracts Manager, NI Water
NI Water Logo
AC Automation provides expert servicing and maintenance across our generator and electrical infrastructure, with a depth of capability spanning LV and HV systems and SCADA control. Their SCADA project at Belfast City Hospital has transformed how we manage our electrical estate and is now being replicated across the Trust.The team — from senior leadership through to the field engineers — are exceptional, and we are always treated as a priority customer.
Stephen LarmourSenior Estates Manager, Belfast City Hospital
Belfast Health and Social Care Trust Logo
AC Automation have provided Generator and associated Control Systems servicing, maintenance and repairs, together with new installations for the South Eastern Health and Social Care Trust Hospitals and Healthcare facilities for over 10 years. Their professionalism and ability to respond 24/7 provides us with confidence and reassurance that we can ensure continuity of essential critical infrastructure. AC Automation bring exceptional technical expertise and experience, are reliable and a welcome team member to solve problems at critical times.
Gerard MorelandSenior Estates Operations Manager, Ulster Hospital
South Eastern Health and Social Care Trust Logo
AC Automation have provided the BHSCT with exceptional generator maintenance and control system development for over 20 years. Their technical expertise, reliability, and proactive support have ensured the resilience and continuity of our critical infrastructure. We highly value their professionalism and trust them as a key partner in maintaining essential services.
Jonny RaveyDivisional Estates Manager, Royal Group of Hospitals
Belfast Health and Social Care Trust Logo

Why Choose Us

Backed by over 35 years of experience, our own in-house engineering team and trusted specialist partners give clients a single point of contact across their wider power infrastructure.

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