When it comes to automatic transfer switches, we use the acronym ATS. In other words, an ATS panel is a metal cabinet that hosts a transfer switch of a suitable size for your standby generator. The ATS controller with its ancillary instruments is normally placed on the metal cabinet's door.

WHAT IS AN ATS CONTROLLER?

There is an abyssal difference between ATS panels and general-purpose generator control panels. The generator control panel only has the basic function of starting the engine and providing real-time protection to prevent severe damage to the engine or generator. The ATS CONTROLLER driver power relays, transfer switches, transformers, electronic boards and all ancillary circuits connect your load to utility power.

Can I use an ATS panel for my house?

Yes, why not. The common answer is to use a suitable ATS panel designed for this purpose. But, if you have a portable generator without a battery you must install an automatic transfer switch panel of a special kind.

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Automatic transfer switch panel working principle

Automatic Transfer Switch Working Principle PDF

The automatic transfer switch panel is conveniently tasked with driving the switching of your load to mains or generators. Even though the power configuration and general arrangement are the same for all panels, the input-output lines for the engine connection and ancillary equipment depend on the type of controller fitted to the panel. The automatic transfer switch panel continuously monitors the status of the utility power. You can set low/high limits for Voltage and Frequency. In other words, when the voltage and the frequency are within limits, the automatic transfer switch panel connects the load to the utility power.

AUTOMATIC TRANSFER SWITCH PANEL TUTORIAL VIDEO

If the voltage drops below the lower limit (or rises above the high limit), the automatic transfer switch panel will disable the utility power circuit. This prevents, after a programmable delay, severe damage to your load. If the failure persists over the programmed time, the ATS panel will instruct the generator to start.

BEFORE CONNECTING YOUR LOAD

The automatic transfer switch panel does its business to check the quality of the generator voltage and frequency. The ATS panel will connect the generator circuit to your load when the parameters are within programmed limits. During a power outage, the automatic transfer switch panel monitors the utility power. When the utility power parameters return within the programmed settings, the automatic transfer switch panel will transfer the load to utility power. This will happen after a delay that will ensure that the utility power is in stable conditions. The engine will run offload after connecting your load to the utility power. Then, the engine will stop and the automatic transfer switch panel is ready for a new power outage.

The automatic transfer switch panel wiring diagram

In the following wiring diagram, you can see all the details about an automatic transfer switch panel. The size of the wires, contactors, transfer switches or changeover, cabinet size, and terminal blocks, depend on power rating. The wiring diagram is the same for all sizes. Download the following documents to find all the answers you are looking for.

What kind of generator can you use with our automatic transfer switch?

Our automatic transfer switch panels support any style of engine and generator. You can upgrade a second-hand generator by using our automatic transfer switch panel.

The internal interface board of our automatic transfer switch panels features all relays that interface with all kinds of engines. In other words, you do not need any controller fitted with your generator. Our automatic transfer switch panel will take care to control all functions. If you own an old generator, check the electric start and stop. In the worst case, you will use two automotive relays to interface with the engine as shown in the below picture

Our automatic transfer switch panel does not need a generator controller placed on your generator!

CAN I MAKE MY OWN ATS PANEL?

Yes, you can. We offer to you a wide range of Automatic Mains Failure and Automatic Transfer Switch Controllers. Visit our website now and choose the product suitable for your application.

HOW TO BUILD AN ATS PANEL TUTORIAL

Why does using our automatic transfer switch panel exponentially increase the long-term reliability of your standby generator?

This is because of a big misunderstanding about overvoltages and flashes of lightning. The low-cost AMF controllers on the market are erroneously placed on the frame of generators. This forces the user to connect the wires of the mains to the controller inside the generator. Despite all your efforts, you will never get protection from the electronic boards. You will not be able to reduce further the parasitic capacitance of the wires.

NEVER DO LIKE THIS WITH AN AUTOMATIC TRANSFER SWITCH

It is a money-saving practice to connect the cables of the mains directly to the AMF controller.

This is an unsafe practice. Forget about it!

CONNECT THE ATS PANEL IN THIS WAY

The overvoltages will never hit your generator.

The controller Be242 will protect your generator from mains surges, You can optionally use your auto-start module, or use the normal input-output lines of the Be242 controller.

What is the difference between an automatic mains failure and an automatic transfer switch panel?

The main difference is that an AMF panel features a CONTACTORS-BASED changeover switch. The automatic transfer switch panel features a MOTORIZED SWITCH-BASED changeover solution. Due to the high cost of the contactors, for large power, it is common sense to manufacture AMF panels up to 80kVA. Over 80kVA we manufacture ATS panels.

How is made an automatic transfer switch?

For current up to 100Amps it is made by using a contactor-based solutions. Over 100 Amps up to 2000 Amps are made by motorized changeover switches.

Contactor-based changeover versus motorized switch-based changeover

You will achieve granular control monitoring and protection of your emergency generator by using two contactors with mechanical interlocks

The contactors, usually four-pole, are coil-operated switches that close a circuit when the excitation coil is supplied with alternating 230V. To keep the contactor in its closed position, it is therefore always necessary to supply the coil. The average consumption is 1oWatt per small contactor but reaches 20 watts for large contactors. This will increase your electricity bill. The life of the coils is expected to be several years. When a coil fails, the contactor does not activate. You must replace the coil. It is not an easy job. Finally, the price of these contactors is reasonable up to a power of 60KVA.

Above this threshold, the contactors are very expensive. There are the panel prices with a contactors scheme up to 60kVA. The great advantage of automatic transfer switch panels with contactors, often called AMF PANELS, is the ability to protect the load very well. They can therefore intervene in switching the network and the generator based on complex settings of timers and priority thresholds. For this reason, the panels equipped with contactors are called AMF panels (Automatic Mains Failure).

How to use the automatic transfer switch?

Our automatic transfer switch panels are based on the Be242 and BeK2/K3 controllers. These are user-friendly controllers. In this example, we describe the way to use the Be242 controller. The BeK2/K3 are strictly similar.

Push the AUTO button. The ATS controller will automatically manage all tasks. The MANUAL button always overrides the automatic way of operation but, in the background, the basic protections will be always active avoiding dangerous situations. The Be242 is a combined ATS, AMF, and generator controller. It offers a large flexibility of use. You can manually start and stop the engine. You can manually control the changeover switch.

THE LOAD IS CONNECTED TO THE MAINS

THE LOAD IS CONNECTED TO THE GENERATOR

PUSH THE AUTO BUTTON TO LET BE242 DOING ITS BUSINESS

The Be242 must be programmed in the factory according to the panel size. You may need to adjust some settings in a way that you adapt the panel to your application. The programming is easy. You can do it by using the navigation buttons on the controller's front panel. You can download the

ATS CONTROLLER INSTALLATION MANUAL

You can connect the panel to any engine. The internal interface board features all the relays you need to start and stop the engine. You can connect the automatic transfer switch panel to a generator fitted with any auto-start module.

How do you connect two generators in a standby configuration?

By using the Be242 automatic transfer switch PANEL you can program the configurable inputs and outputs committed to manage the priority of the start. This is the typical duel generator configuration.

How to serve two separate buildings with the same standby generator?

Forget to use complex PLC when you have to make this kind of application. It is about the DAUL-LOAD configuration, You program this function into the adjustable input-output of the controller.

A BeK2-based automatic transfer switch panel

Over 80kVA we manufacture ATS panels with motorized changeover switches. An ATS panel with power between 80kVA and 160kVA features the BeK2 controller. Here is an example of a generator control panel fitted with a BEK2 controller [1]. The panel controls the engine via the programmable input-output lines [4]. The BEK2 interfaces with switches fitted to the generator's frame [3]. The generator control panel is connected to the alternator via a power cable of a suitable size. According to the mode of operation, the BEK2 controller drives the status of the internal power circuit breakers.

THE BEK3 CONTROLLER

The BeK3 controller features MODBUS and CANBUS (SAEJ1939 compatible). You can use traditional standard engines by programming the input/output lines.

The panel includes miscellaneous equipment: a battery charger, electronic circuit boards, power relays, and terminal blocks. The BeK3 controller is conveniently tasked with driving the contactors. These BEK3-based panels feature IP62 ingress protection.

A BeK3-based ATS panel offers monitoring options

The BeK3 automatic transfer switch offers superior remote control monitoring capabilities over any competitors.

GENERATOR REMOTE CONTROL MONITORING TUTORIAL

We offer solutions to monitor fuel levels via GSM, TCP/IP and MODBUS. We offer free of charge software tools.

Watch the be242 presentation video

A BE242-BASED ATS PANEL FEATURES:

Are you looking to develop your business by making automatic transfer switch panels?

When you make an automatic transfer switch panel, install the Be242 ATS controller, a changeover switch, a battery charger, and a set of terminal blocks. Put current transformers if you are willing to set up the overload protection. Assemble all parts following our tutorial. With Be242, you no longer need other components when making an automatic transfer switch panel. The result is an enormous saving in time, materials and money!

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Using the Be242 controller you can afford to make your own ATS panels. The controller is designed to simplify the process of manufacturing,

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