How many volts is used in a high voltage AC secondary circuit?

Generally, the voltage of the secondary circuit is 24V or 48V signal power supply, 220V protection power supply and operating power supply.

The cabinets installed in the same place are connected by small busbars, the cabinets installed in different locations are connected with cables, and the signal loops are connected with shielded cables.

Secondary Loop Definition:

Measuring loops, relay protection.

Circuits, switch control and signal circuits, operating power circuits, circuit breakers and disconnectors.

electrical locking circuits and other low-voltage circuits. The electrical circuit that is connected by secondary equipment to form monitoring, controlling, regulating and protecting primary equipment is called secondary circuit. is in the electrical system by the transformer.

secondary windings, measuring and monitoring instruments, relays.

A circuit that is connected by a control cable, such as an automatic device. It is used to control, protect, regulate, measure and monitor the working conditions of each parameter and each component in the primary circuit. The circuit used to monitor the electrical connection of the meter, control operation signal, relay protection and automatic device is called a secondary circuit.

The B phase voltage of the secondary circuit is 0V, when is the key to see the wiring method of the voltage transformer, for the voltage transformer to use the "V" type connection method, the primary side of the two voltage transformers A

Generally, the voltage of the high-voltage secondary circuit is 100V, which is safe to use and easy to calculate.

Hello The current loop and the voltage loop can be found from their circuit number. The circuit number of the current circuit is prefixed with "4", such as "A411, B411, C411", etc. The circuit number of the current circuit is prefix "6", such as "A630, B630, C630" and so on.

110kv substation has those secondary circuits.

The secondary circuit of the 10kV high-voltage distribution cabinet is generally 220V DC, which draws power from other DC systems. If it is not an important switchgear, 220V AC is used, and a small-capacity transformer is generally set on the bus, and AC is drawn from the secondary side as a protective power supply.

DC is the DC screen for the secondary circuit power supply of the 10kV high-voltage distribution cabinet, AC is to add PT to the incoming line, and then use the intermediate transformer of 100 220V to power the power.

The secondary circuit in the high-voltage distribution generally adopts AC power supply, and the mutual inductance is converted into direct current, so that there is no need to configure the DC power supply, reduce the area demand of the distribution room, the cost of equipment purchase, and reduce the cost.

Actually, it's not that difficult. It is mainly divided into incoming cabinet line protection, outlet cabinet transformer protection, PT cabinet insulation monitoring, PT parallel contact cabinet, self-investment, etc.

The protection of the secondary circuit is mainly divided into: incoming line protection, outgoing transformer protection, ordinary outgoing line protection, capacitor protection (reactive power compensation, hurry up), PT parallel device, standby self-throwing (now there is a quick cut), insulation monitoring.

Incoming protection can be protected with three-stage overcurrent.

The transformer can be used: gas protection, differential protection and backup protection, and ordinary outgoing lines are protected by three-stage protection.

The capacitor is an overload and three sections, plus a high and low voltage protection.

PT tie will not be said.

You can choose the method of entering the line of standby investment.

Some can, but some can't, it mainly depends on the circuit function and the orientation of the power supply!

The biggest reason is that the uninterruptible power supply can only be DC power supply.

Secondly, the design of the secondary original in many devices is DC.

You can also use AC as a secondary power source! The key to this is whether the action coil and the secondary element are DC or AC! You also need to consider whether to use PT power supply or DC screen power supply!

Compared with AC, the DC power supply is relatively stable, the voltage is adjustable, and the battery can be equipped to improve the reliability of the DC power supply system.

Because the high-voltage control bus, closing bus, measurement and control device power supply, protection device power supply and multiple intermediate relays are DC power supplies, the use of DC panel power supply is more safe and reliable.

Security Measures:

Before the first and second circuits are energized or withstand voltage test, the attendant and relevant personnel should be notified, and someone should be sent to guard the scene, check the circuit, and confirm that no one is working before pressurization.

2. The staff who inspect the power-off protection and the secondary circuit are not allowed to carry out any reverse operation without the permission of the personnel on duty.

3. Strictly prevent short circuit or grounding.

4. Insulated tools should be used, insulated gloves should be worn, and the relevant relay protection devices should be deactivated before work if necessary.

5. When connecting temporary loads, special switches and fuses must be installed.

6. During the energizing test of the secondary circuit, in order to prevent the reverse voltage from the secondary side to the primary circuit, in addition to disconnecting the secondary circuit, the primary fuse should also be removed.

Power outages, power outages are not allowed, insulated protective gear must be worn, insulated shoebox insulated gloves must be worn.