What is ATS? What is its function?
ATS is short for Automatic Transfer Switch.
Automatic Transfer Switch is a power switching device that automatically switches between two power sources. Typically, Power 1(also referred to as the primary power, main power or normal power) is the utility power, and Power 2(also referred to as the secondary power, standby power or backup power) is the generator.
When the Power 1 fails, the ATS switches to Power 2 automatically.
What will happen if the Utility Power restores?
Automatic Transfer Switch will switch to Utility Power from Generator Power. This is known as Auto-transfer and Auto-retransfer.
Auto-transfer and Non-auto retransfer function can be atprovided upon specific customer request.
Can I operate ATS manually?
Yes, every ATS is equipped with one unit of manual handle. Before you operate manually, the ATS needs to be set to Manual Mode.
Additionally, the operate direction is indicated on the switch body.
PC Class originally meant “Power Contactor.” But today, it does not mean the ATS is built with contactors.
According to the International Electrotechnical Commission (IEC 60947-6-1):
PC Class ATS is a device used for power switching only, without built-in short-circuit protection.
Read more in this article PC ATS vs CB ATS
What does 2P ATS, 3P ATS or 4P ATS mean? What does P stand for?
In the context of electrical switches like an ATS (Automatic Transfer Switch), the P stands for Pole.
A Pole refers to the number of separate electric circuits or conductive paths that the switch can control simultaneously.
A 2P (Two-Pole) switch is typically used in single-phase electrical systems. It switches two wires: 1. The Live (Phase) wire；2. The Neutral wire.
By using a 2P ATS, you ensure that the Neutral connection is also transferred or isolated when switching between the main power and a generator. This is often a safety requirement in many regions to prevent "stray" currents from returning through the neutral line.
2P: Used in Single-phase Two-wires power systems(Single Phase+Neutral);
3P: Used in Three-phase Three-wires power systems(Thress Phases: L1, L2, L3 or A, B, C);
4P: Used in Three-phase Four-wires power systems(Three Phases+Neutral).
Why "Pole" matter for Automatic Transfer Switch?
When selecting an ATS, the pole count must match your power system and local wiring regulations (such as IEC 60947 standards).
For example, in industrial applications where grounding systems are strictly monitored, a 4P ATS is often preferred over a 3P version because it provides full isolation of the Neutral, preventing potential ground loop issues between the utility and the backup generator.
Do I need a high-speed ATS?
It depends on the load type. In most cases, high-speed ATS is not necessary. It is only necessary for precision equipment that cannot tolerate even the slightest power interruption.
Are ATS and ATSE the same thing?
Not exactly—they are closely related, but not identical.
ATS (Automatic Transfer Switch) is a widely used industry term referring to a device that automatically switches between two power sources, such as utility and generator power. It’s commonly used in marketing and everyday communication.
ATSE (Automatic Transfer Switching Equipment), on the other hand, is a more formal and standardized term defined in standards like IEC 60947-6-1. It refers to the complete equipment, including the switch, controller, and related components.
In simple terms: ATS is the common name, while ATSE is the formal, standard-defined term.
How does ATS work with power generators?
AISIKAI ATS solutions integrate high-reliability Intelligent Control Units, enabling the system to not only detect total utility failure in real-time but also provide precise diagnostics for complex grid environments.
The ATS system responds instantaneously to power outages. When equipped with AISIKAI ATS Controllers, the precision algorithms further extend protection by monitoring under-voltage, over-voltage, and phase loss. This ensures the generator is signaled to start only at the most critical and appropriate moments.
Upon detecting a utility anomaly, the controller immediately sends a start signal to the generator. Once the generator reaches its rated speed and voltage, the ATS mechanism safely disconnects the utility source and simultaneously closes the generator circuit.
Within seconds, the AISIKAI system restores power to your home or business's emergency circuits. Throughout this period, the controller maintains "thermal monitoring" (active sensing) of the utility line conditions.
Can an ATS start diesel generator?
No, this is not the function of ATS. If you need to start diesel generator, a generator controller is needed.
Can AISIKAI ATS work with Photovoltaic (PV) Systems?
Yes, absolutely. AISIKAI ATS is designed for multi-source power management and is fully compatible with PV systems. Its core functions include:
Seamless Switching: Automatically switches between Utility, PV Inverter, and Backup Generator to ensure 24/7 power continuity.
System Protection: Built-in mechanical and electrical interlocks prevent backfeeding and protect your solar inverters.
Smart Logic: When used with AISIKAI controllers, the system can prioritize solar energy and only trigger the generator or utility when battery or PV output is insufficient.
