An Automatic Transfer Switch (ATS) is the critical component that makes a backup generator system actually automatic. Without an ATS, someone has to manually start the generator and flip the switch during a power outage — which defeats the purpose of having backup power for a data centre that needs 99.99% uptime. For facilities in Malaysia where grid interruptions can happen during monsoon season, scheduled TNB maintenance, or equipment failure, an ATS ensures your diesel generator takes over within seconds, keeping servers, cooling, and network equipment running without interruption.

This guide covers everything you need to know about ATS panels for data centre and server room generators in Malaysia — types, sizing, compliance, installation, and pricing. MGM Generators supplies ATS panels matched to our generator range from 15kVA to 500kVA, with professional installation and commissioning across Peninsular Malaysia.

What Is an Automatic Transfer Switch (ATS)?

An ATS is an electromechanical device that continuously monitors the utility (TNB) power supply. When it detects a power failure — voltage drop below threshold, complete outage, or phase loss — it automatically:

  1. Sends a start signal to the backup generator
  2. Waits for the generator to reach stable voltage and frequency
  3. Transfers the electrical load from utility to generator
  4. Monitors the generator while it runs
  5. When utility power is restored, transfers the load back and sends a cool-down signal to the generator

The entire transfer process takes 10–30 seconds depending on the ATS type and generator starting time. For data centres with UPS systems bridging the gap, the actual server downtime is zero — the UPS covers the milliseconds of transfer time.

Types of ATS for Data Centre Generators

Open Transition ATS (Break-Before-Make)

The most common and affordable type. The ATS disconnects from utility before connecting to the generator, creating a brief power gap of 50–100 milliseconds. For data centres, this gap is covered by the UPS, so servers experience no interruption. Suitable for Tier II and Tier III facilities.

Closed Transition ATS (Make-Before-Break)

The ATS briefly connects both utility and generator simultaneously (for less than 100 milliseconds) before disconnecting from utility. This eliminates the transfer gap entirely — no momentary dropout, no UPS activation needed. Required for Tier III+ and Tier IV data centres where even a flicker is unacceptable.

Static Transfer Switch (STS)

Uses solid-state electronics (SCRs) instead of mechanical contacts. Transfer time is less than 4 milliseconds — fast enough that even sensitive servers do not register the switch. STS units are used in the most critical data centre applications and typically work between two independent power sources (utility + generator, or two UPS systems).

For most Malaysian data centres, a closed-transition ATS provides the best balance of reliability and cost. MGM’s ATS panels are available in open-transition and closed-transition configurations for all generator sizes.

ATS Sizing for Data Centre Generators

The ATS must be rated for the full load current of your data centre. Sizing is based on the generator’s kVA rating and the operating voltage:

  • 50kVA generator (415V 3-phase) ? 70A ATS panel
  • 100kVA generator (415V 3-phase) ? 140A ATS panel
  • 250kVA generator (415V 3-phase) ? 350A ATS panel
  • 350kVA generator (415V 3-phase) ? 490A ATS panel
  • 500kVA generator (415V 3-phase) ? 700A ATS panel

Always select an ATS rated at least 125% of your maximum load current to handle motor starting inrush and future expansion. An undersized ATS will trip under heavy load, defeating the entire backup system.

Each MGM generator comes with a matched ATS option. For example, the 100kVA MGM Generator pairs with a 200A ATS panel, while the 500kVA MGM Generator requires an 800A ATS for full-load transfer.

ATS Installation in Malaysian Data Centres

Automatic Transfer Switch panel installation in Malaysian data centre backup power system

Proper ATS installation requires attention to Malaysian regulatory and site requirements:

  • TNB approval — Parallel operation with the grid (closed-transition) requires TNB notification and approval. Open-transition ATS does not require TNB sign-off since it never connects both sources simultaneously.
  • Electrical inspection — All ATS installations must be inspected by a registered electrical contractor (Wireman or Chargeman) under the Electricity Supply Act 1990.
  • Fire safety — Jabatan Bomba requires clear access to electrical panels and proper labelling for emergency shutoff in data centre environments.
  • Placement — ATS panels should be installed between the TNB meter and the main distribution board (MDB), in a dedicated switchgear room with adequate ventilation and clear floor space per MS IEC 61439 standards.

MGM Generators handles the full installation process including TNB coordination, electrical inspection, and commissioning. Our team ensures your generator and ATS system is fully compliant and tested before handover.

Get an ATS Quote for Your Data Centre

Choosing the right ATS for your data centre or server room? Call +6012 9689816 or WhatsApp us to discuss your current setup, load requirements, and redundancy needs.

Visit our contact page for a detailed ATS and generator proposal tailored to your facility’s power requirements and compliance needs.