GGJ Reactive Power Compensation Device
The reactive power compensation device in the power supply system improves the power factor of the power grid, reduces losses in the power supply transformer and transmission lines, increases power supply efficiency, and improves the power supply environment.
A GGJ reactive power compensation device is the capacitor-bank cabinet that runs alongside a low voltage switchboard line-up — switching capacitor steps in and out automatically to lift the power factor of the network, cut reactive losses across the supply transformer and lines, and ease the demand charges and capacity penalties that utilities apply to poorly compensated installations. It is the natural companion to fixed-type boards such as GGD, coupling to the same busbar system in a continuous row.
We build GGJ compensation cabinets to the target power factor and load profile of each site — step sizing, controller settings, and reactor selection engineered per project rather than sold off the shelf. Since 2010 our workshop has delivered more than 4,000 enclosure and distribution projects, with CNC punching, bending, and welding in-house, so capacitor cabinets arrive wired, tested, and ready to couple with your main board.
The switching stages at the heart of a GGJ cabinet are power factor correction capacitors: each power factor correction capacitor bank is switched in or out by the automatic controller to track the reactive demand of the load, holding the power factor at the target set on the regulator.
feature of GGJ Reactive Power Compensation Device
After capacitor compensation
Increase the voltage of busbars and feeders.
Reduce the total current flowing into the power station.
Increase the load capacity of the transformer.
Improve the unit's power factor.
Reducing the transmission of reactive power on distribution lines can reduce power losses on distribution lines.
Tap the potential of the equipment, improve the output of the equipment, and fully improve the utilization rate of the equipment.
GGJ Reactive Power Compensation Device Dimensions
| Name | Parameter |
|---|---|
| Overvoltage category | IV III |
| 3 | |
| 280 (660) | |
| Rated insulation voltage (V) | 660 (1000) |
| 50 (60) | |
| Rated current | 5000A 4000A 3150A 2500A 2000A 630A |
| Rated short time withstand current (kA) | 50, 65, 80 |
| Rated peak withstand current (kA) | 105, 140, 176 |
| Vertical Busbar | |
| Rated max working current | 1000A |
| Rated short time withstand current (kA) | 50kA |
| Rated peak withstand current (kA) | 105kA |
| Outshell protection class | IP30 IP40 |
Key Specifications & Options
The configuration below reflects the options we build to order for GGJ reactive power compensation devices. Every parameter can be adjusted to match your drawings and site conditions — send us your requirements and our engineers will confirm what applies to your project.
| Parameter | Options / Typical Range |
|---|---|
| Compensation type | Low voltage shunt capacitor banks with automatic or manual step switching |
| Rated voltage | AC 50 Hz, 400 V class low voltage systems |
| Compensation capacity | Step sizes and total kvar engineered to your load profile and power factor target |
| Switching devices | Capacitor contactors as standard; thyristor switching for fast-cycling loads |
| Detuning | Reactor options where harmonic-rich loads are present in the network |
| Controller | Automatic power factor controllers with current-transformer measurement |
| Step protection | Fuses, discharge devices, and thermal monitoring per step |
| Applicable standards | GB 7251 series for LV assemblies, corresponding to IEC 61439 |
Frequently Asked Questions
What does a GGJ cabinet do inside a switchboard line-up?
It supplies the reactive power your inductive loads — motors, transformers, welders — otherwise draw from the grid. Mounted beside the main board and coupled to its busbars, it switches capacitor steps automatically to hold the power factor near target, which reduces line losses and helps avoid low power factor penalties on the utility bill.
How is the compensation capacity decided?
From the gap between your present and target power factor together with the load profile — measured kvar demand, load variation, and harmonic content. We size the total kvar and split it into steps so the controller can follow the load without hunting; a share of the transformer rating is the usual starting point, confirmed by your load data.
Contactor or thyristor switching — which do I need?
Capacitor contactors suit loads that change over minutes and cost less; thyristor switching responds within cycles for rapidly fluctuating loads such as welding lines and cranes, avoiding the inrush and switching transients that wear contactors. Most industrial boards start on contactors and add a fast step where the profile demands it.
Which standards apply to GGJ assemblies?
Low voltage capacitor assemblies fall under the GB 7251 series for LV switchgear and controlgear assemblies, which corresponds to the IEC 61439 series. We reference these standards in design and supply assembly documentation with the cabinet.
Related Guides
- Low-Voltage-Switchgear Guide: Functions, Types, and Selection Inputs — where compensation fits in the LV switchgear family
- Understanding the Differences Between High, Medium, and Low Voltage Switchgear — voltage-class context for the LV line-up
- Power Distribution Panel Guide: Components, Functions, and Selection Inputs — component-level guide to the distribution boards GGJ serves
- GGD Low Voltage Fixed Switch Cabinet — the fixed-type main board this compensation cabinet pairs with
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