Automatic Changeover-cum-Current Limiter(ACCL):
ACCL is a fully automatic, high-precision system installed in apartments, residential complexes, and commercial buildings. It has the following functions:
- The ACCL allows unrestricted power on Mains. If both EB and DG supplies are available, EB is given preference
- When EB fails and the standby Generator is ON it transfers the load to DG and begins monitoring the load. While on DG, if the load current exceeds a pre-set limit, the output trips. Other consumers who are within limits continue enjoying uninterrupted DG power. After 8/10/12 seconds, the load is reconnected and monitored again. If the current drawn has been reduced by switching off unneeded appliances, supply continues, else, it trips again.
- When EB gets restored, the ACCL automatically disconnects the load from DG and transfers it to EB.
Features and Benefits:
- Microcontroller-based design for superior performance, replacing outdated manual systems at no extra cost.
- No separate wiring required.
- Available in single-phase and 3-phase configurations, up to 125A capacity.
- DG metering (Class 1.0) models with RS-485 connectivity available.
- Assured availability of allotted current – no less, no more. Ensures equitable rationing of generator power.
- DIN channel mountable enclosures save space and make installation hassle-free.
- Display key parameters such as current, voltage, pre-trip, and trip indication.
- Best-in-class design and aesthetics.
- Fire-retardant polycarbonate body for increased safety.
- Simple operation with a clear indication of states — set it and forget it!
Automatic Changeover Switches
Automatic changeover switches are electrical switches that change over or switch a load between two sources. In the case of automatic switches in contrast to manual switches, the switches get triggered when they sense one of the sources has either gained or lost power.
Installation is usually done where a backup generator is located for it to provide temporary electrical power if the utility source fails. The load automatically shifts to generator supply when the main supply fails, and when the mains supply restores the load shifts back to mains and the generator becomes unloaded. When the utility line returns at a steady-state, the automatic switches sense it and re-transfer the electrical load back to the line and continue monitoring for subsequent utility loss.
The changeover switching function signifies a unique version of a pressure switch with two switching outputs acting oppositely to switch two circuits. Changeover switches close one circuit and simultaneously opens a second circuit. These switches are able to supply maximum current for about three or more hours to a continuous load. It is easily capable of handling current to critical loads continuously from the emergency power source. The present ratings range from 30 to 400 amperes.
Automatic changeover switches fall under the categories of many types of transition switches out of which, open transition switches are the first in the list. During the power transfer procedure, within a split second of time, the flow of electricity is interrupted in such switches. It averts and inhibits back feeding from an emergency generator going back into the utility line and breaks contact with one source of power before it forms contact with others.
Automatic changeover switches also come under closed transition switches, soft loading switches, and standard loading switches. Closed transition switches are basically the make-before-breakfast switches in which a typical emergency system uses the open transition to create an inherent momentary interruption of power to the load when transferred from one source to another source. In soft loading switches, coordinating, matching, and operating onsite generation in correspondence with utility power takes place to transfer loads amid the sources while reducing the voltage or frequency transients are involved in the procedure. Static transfer switches use power semiconductors to shift a load between two sources and the transfer can be finished fast since there are no mechanical moving parts involved.
For businesses that involve large production or are working on a large scale, automatic changeover switches are the go-to solution for it. Since these corporations and industries can not afford interruptions, automatic changeover switches are highly recommended.