Generator Synchronization Panel

A generator synchronization panel is the control and power panel that allows several generators to run in parallel with each other or with the grid. The panel matches the voltage, frequency and phase angle of the generators, connects the sets to a common busbar and shares the total load between them. Instead of one large generator, several sets that come online and go offline as required supply the same site.

We design synchronization panels for each project, manufacture them at our facility in Türkiye, and test and commission them together with the generator sets.

How does a synchronization panel work?

The controller of each generator to be paralleled continuously measures the busbar voltage and frequency. When a generator is to be brought online, the following steps take place:

1. Start and run-up: The generator starts and reaches rated speed and voltage.
2. Matching: The controller adjusts engine speed and alternator voltage so that the generator’s voltage, frequency and phase angle match the busbar. Phase sequence is also checked.
3. Breaker closing: As soon as the values are within the permitted limits, the generator breaker closes and the set is connected to the busbar.
4. Load sharing: The connected sets share active power (kW) and reactive power (kVAr) in proportion to their ratings.
5. Load management: When the load rises, the next generator comes online automatically; when the load falls, a set that is no longer needed transfers its load, goes offline and stops after its cool-down period.

These operations run without operator intervention, through communication between the controllers. You can find the technical details of parallel operation in our article on generator synchronization and paralleling.

Operating modes: AMF, ATS and synchronization

Operating mode	What it does	Typical use
AMF (automatic mains failure)	Starts a single generator when the mains fails and stops it when the mains returns	Single-generator standby power
ATS transfer panel	Transfers the load between the grid and the generator; the two are never connected to the load at the same time	Standby power for buildings and facilities
Generator-to-generator synchronization	Connects several sets to a common busbar and shares the load	High power, redundancy, variable load
Parallel operation with the grid	Connects the generator to the same busbar as the grid; no-break return or base-load generation	Industry, cogeneration, peak load management

In single-generator applications, the control panel on the set and an ATS transfer panel are sufficient for mains monitoring and automatic start. A synchronization panel is used when several sets will run together or when the generator must run in parallel with the grid.

Standard control panel and synchronization controllers

On Terex Diesel generator sets, the standard control panel is determined by the power in the model code:

• Sets below 500 kVA: Datakom DKG-309
• Sets of 500 kVA and above: Datakom D-500

These controllers handle mains monitoring, automatic start and engine protection for a single set. Synchronized systems use one of the synchronization controllers in our product catalogue:

• Datakom: D500 MK2, D700
• Deep Sea: 8610, 8620, 8660
• ComAp: InteliCompact NT SPtM, InteliGen BaseBox, InteliGen 200

The controller is chosen according to the number of sets, the need for parallel operation with the grid, and the communication requirements for remote monitoring and automation systems. A feature comparison of all controllers is on our generator controllers page.

What is inside the panel?

Each synchronization panel is configured for its project. A typical panel includes:

• A motorised breaker and a synchronization controller for each generator
• A common busbar and, where required, a mains breaker
• Current and voltage transformers, metering and protection relays
• Load sharing and set priority sequencing (automatic rotation that balances running hours)
• Emergency stop, alarm and warning signals
• Remote monitoring connection (GSM, Ethernet or building management system)

The enclosure, breaker ratings and protection settings are selected according to the site’s short-circuit level and total power.

Why several generators?

• Redundancy: When one set fails or is under maintenance, the others continue to supply critical loads.
• Efficient operation at low load: When the load drops, a single set runs; problems caused by running a large generator at low load for long periods are avoided and fuel consumption is reduced.
• Phased expansion: When the site’s power demand grows, new sets can be added to the existing system.
• Easier maintenance: Running hours are shared between the sets, which makes maintenance planning easier.

For projects that require two synchronized sets on a single base frame, we also offer dual generator sets, for example 2 × 1000 kVA on one base frame for a 2000 kVA requirement.

Where is it used?

Synchronization panels are used in projects with high or variable power demand that cannot tolerate interruptions:

• Data centres and telecoms infrastructure
• Hospitals and healthcare campuses
• Industrial plants and organised industrial zones
• Shopping centres, hotels and large commercial buildings
• Mining sites and off-grid projects
• Cogeneration and medium voltage systems

Power ranges

The sets used in synchronized systems are selected from the diesel generators in our product catalogue, covering 10–4,125 kVA. For ratings frequently chosen in high-power projects, see our 500 kVA, 1000 kVA, 1500 kVA and 2000 kVA generator pages. Sets up to 1,100 kVA are supplied with a soundproof canopy, and larger sets as containerised generators.

Custom manufacturing and commissioning

A synchronization project starts with a clear definition of the requirement. The following information helps us prepare a quotation:

• Total power demand and the number of sets
• Whether parallel operation with the grid is required, or only the generators will be synchronized
• Voltage and frequency (50 Hz or 60 Hz)
• Make, model and controller details of any existing sets
• Requirements for remote monitoring or building management integration

Panel manufacturing, on-site installation, cabling, automation integration, testing and commissioning are carried out by our own teams. To add synchronization to existing generators, see our ATS and synchronization retrofit service; for installation, see installation and commissioning. Request a quote for your project or talk to our service team.