BE1-51, BE1-51/27C, BE1-51/27R — maximum current protection relays with voltage-controlled and voltage-restrained pickup
BE1-51, BE1-51/27C and BE1-51/27R are microprocessor time-overcurrent protection relays for 50 and 60 Hz networks. Versions with voltage-controlled and voltage-restrained pickup are available for generator protection, along with 16 selectable time-current characteristics.
- Frequency
- 50 / 60 Hz
- Inputs
- one phase; two phases + neutral; three phases; three phases + neutral
- Characteristics
- 16 selectable curves
- Versions
- BE1-51; 51/27C (voltage-controlled pickup); 51/27R (voltage restraint)
Price, availability and lead time on request. We help with analogue selection, customs clearance and delivery.
Description
BE1-51 is a microprocessor time-overcurrent protection relay. It protects against overloads and short circuits in 50 and 60 Hz networks and is used in utility networks, industry and power generation. The higher the current, the faster the relay operates, and the shape of this dependence is set by the selected time-current characteristic. The time delay is coordinated with other protection devices by choosing one of 16 characteristics on site. The pickup setting is smoothly adjustable over a wide range.
The input configuration is chosen to suit the system scheme: single-phase, two-phase with neutral, three-phase and three-phase with neutral. According to the manufacturer's catalog, the BE1-51, BE1-51/27C and BE1-51/27R are produced in single-phase, three-phase and three-phase with neutral versions, while the BE1-51 is also available in a two-phase with neutral version.
For generator protection there are the BE1-51/27C, which uses voltage-controlled pickup (voltage control), and the BE1-51/27R, which uses voltage restraint. During a close-up short circuit the generator current drops quickly to a value close to rated. Therefore a relay with voltage control keeps its sensitivity to such faults.
The relays have a low burden on the current and voltage transformer circuits, which reduces the requirements for measuring transformers and the cost of current transformers. The power supply places a small load on the station battery. The relays are set through a simple interface without a computer, the status is shown by LED indication, and the device can be tested in its case with test plugs. The relays are noted for precise and repeatable operation. For generators the voltage-controlled or voltage-restrained versions are selected, and for the remaining feeders the BE1-51 with the required number of phases and neutral is chosen. The manufacturer's catalog presents the relay as universal protection against overloads and short circuits, which can be adapted to the task by choosing the version and the characteristic.
For complex installations the BE1-51 functions are included in the multifunction BE1-11 and BE1-FLEX systems, and for installations without an auxiliary supply there are self-powered BE1-50/51 relays. The relays are used to protect feeders, transformers, generators and motors, and as backup protection. The devices are designed and manufactured at plants in Highland, Illinois and Taylor, Texas.
Technical specifications
| Frequency | 50 / 60 Hz |
|---|---|
| Inputs | one phase; two phases + neutral; three phases; three phases + neutral |
| Characteristics | 16 selectable curves |
| Versions | BE1-51; 51/27C (voltage-controlled pickup); 51/27R (voltage restraint) |
| Current setting | smoothly adjustable over a wide range |
Request a price and lead time
BE1-51, BE1-51/27C, BE1-51/27R — maximum current protection relays with voltage-controlled and voltage-restrained pickup. We reply within one business day.
Or email sales@usk.ua or call 044 339-50-20.
Questions and answers
Which networks are the BE1-51 relays intended for?
The relay protects against overloads and short circuits in 50 and 60 Hz networks. It is used in utility networks, industry and power generation.
How do the BE1-51/27C and BE1-51/27R differ?
The BE1-51/27C operates with voltage-controlled pickup (voltage control) and the BE1-51/27R with voltage-restrained pickup (voltage restraint). Both are intended for generator protection, where the current drops quickly during a close-up short circuit.
How many time-current characteristics and which input configurations are available?
There are 16 selectable time-current characteristics. The inputs are configured as single-phase, two-phase with neutral, three-phase or three-phase with neutral.
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