When a three-phase main supply is being used with single-phase loads, the availability of phases is an important part of the supply arrangement. At Selfguard, our Automatic Phase Changer (APC) is designed specifically for a Three Phase Main Supply with Single Phase Loads. The unit gives output on all three phases even when only one phase or two phases are present.
How the Selfguard Automatic Phase Changer Works
The Selfguard Three Phase Automatic Phase Changer is installed with a Three Phase Main Supply only. Its stated function is to give output on all three phases when either one phase or two phases are present.
For example, when one of the phases is missing and two phases are present, the APC continues to give output on all three phases. Similarly, the unit is designed to give output on all three phases even when only one phase is present. This is the main operating function of our Automatic Phase Changer.
The unit is specifically applicable to a Three Phase Main Supply and Single Phase Load only. According to our product specifications, examples of these single-phase loads include:
- Lights
- Fans
- Single Phase AC
- Single Phase Motors
These examples define the type of loads for which the Selfguard APC is intended.
What Happens When the Missing Phase Comes Back?
The operation of the APC also includes automatic load shifting when the missing phase becomes available again.
When any missing phase comes back, our Automatic Phase Changer automatically shifts the load back to its original phase. This shifting takes place with the unit’s inbuilt delay timer.
Therefore, the Selfguard APC performs two clearly stated functions. It gives output on all three phases when only one or two phases are present, and when the missing phase comes back, it automatically shifts the load to its original phase with the inbuilt delay timer.
Designed for Three-Phase Mains and Single-Phase Loads
The intended application of the Selfguard APC is important when selecting the product. Our Automatic Phase Changer is designed for use with a Three Phase Main Supply and Single Phase Loads only.
This makes the type of main supply and connected load important considerations when choosing the unit. Selfguard specifies that selection of the Automatic Phase Changer should be made according to the load of the mains.
Available Automatic Phase Changer Ratings
To meet different mains load requirements, the Selfguard Automatic Phase Changer is available in several current ratings:
63 Amps | 100 Amps | 125 Amps | 150 Amps | 200 Amps
The 63 Amp APC has a listed size of 300 × 250 × 115 mm, while the 100 Amp, 125 Amp, 150 Amp and 200 Amp models have a listed size of 375 × 310 × 135 mm. The appropriate APC is selected according to the mains load.
Selfguard Automatic Phase Changer
At Selfguard Automation and Controls, we have been engaged in manufacturing electrical and electronic products related to mains, generator and agricultural automation since 1990.
Our Automatic Phase Changer, Item Code APC, is designed for three-phase mains installations with single-phase loads. When only one or two phases are present, the unit gives output on all three phases. Once a missing phase comes back, the APC automatically shifts the load to its original phase using its inbuilt delay timer.
With ratings ranging from 63 Amps to 200 Amps, the Selfguard Automatic Phase Changer can be selected according to the load of the mains.