What is interlocking in substation?
1 Substations shall be provided with a full interlocking scheme to ensure that all disconnectors, fixed earthing switches (or other interlocked earthing devices) and, where required, circuit-breakers are operated in the correct sequence so that personnel do not endanger themselves and/or the integrity of the …
What is interlocking in electrical system?
An interlock device is designed to allow a generator to provide backup power in such a way that it (a) prevents main and generator power to be connected at the same time, and (b) allows circuit breakers to operate normally without interference in the event of an overload condition.
What is interlock in circuit breaker?
The purpose of mechanical interlocked circuit breakers is to prevent power sources from being connected to the load at the same time. The interlocking system prevents the handle from moving from the Off position to the On position, disabling one circuit breaker.
What are the major equipment of a substation?
Distribution Transformer. Circuit breaker. Lightning Arrester. Air Break (AB) switches / Isolator.
How many types of interlocks are there?
There are two main types of interlocks: safe and non-safe. Some systems require safe and non-safe interlocks to create a control system.
Why interlocking is used for the contactors?
A technique called interlocking is used to prevent the contactors from being energized simultaneously or closing together and causing a short circuit. This interlock locks out one contactor at the beginning of the stroke of either contactor to prevent short circuits and burnouts.
What are the types of interlock?
In segmental retaining wall construction, there are 4 types of interlock:
- Shear strength.
- Independent or dependent mechanical device.
- Void fill.
- Pattern.
How do you do electrical interlocking?
To interconnect the motor circuit in such a way, in which the second motor will not start until the first one run likewise the third one motor will not run unless the second one run and so on. This kind of motor circuit connection is called interlocking. A simple electrical interlocking control diagram is shown below.
What are the two types of interlocks in industrial control?
The types of interlocks in the System are described below….Permissive Interlock
- DCS System Layout.
- ICS Control System.
- PLC Permissive Interlocks.
- Interlocking in PLC.
- PLC, HMI, VFD, and Motor.
What is the difference between a power circuit and a control circuit?
A device that controls the flow of electrical power to a motor. In contrast to the Power Circuit, the Control Circuit consists of inputs, in the form of switches, pushbuttons or pilot devices, which when activated, can either directly, or through a magnetic motor starter, energize a load.
What are the three main parts of a substation?
Elements of a substation
- Primary power lines.
- Ground wire.
- Overhead lines.
- Transformer for measurement of electric voltage.
- Disconnect switch.
- Circuit breaker.
- Current transformer.
- Lightning arrester.
What type of transformer is used in substation?
1. Substation Transformers. Used with outdoor substations, they are rated 750-5000 kVA for single-phase units and 750-25 000 kVA for three-phase units. High voltage transformer 40MVA (Steps down 150kv to 10kV in a substation in Belgium.
How are system protection schemes used for power substations?
The scheme for a system protection is used at small-size power substations. A detailed explanation of the frame earth protection, differential protection, and reverse interlocking protection for busbars is discussed further. 1. System protection used to cover busbars
How does zone interlocking work in a power distribution system?
In a coordinated system, only the device nearest to the fault will trip unless the coordinated protection levels are exceeded. Zone interlocking works in parallel with the coordinated protection of a power distribution system, meaning the nominal protection levels are not compromised. Zone Interlocks communicate fault conditions across zones.
What is the purpose of zone selective interlocking?
Zone selective interlocking is a communication scheme used with circuit breakers and protective relays to improve the level of protection in a power distribution system.
When do differential protection schemes for distribution substations?
The applied logic enhances performance of the relay while keeping an excellent balance between dependability/speed and security. When a differential protection is employed for sectionalized busbars it is required that divided bus utilizes separate circulating current.