Basler Electric BE1-32R, BE1-32O/U Directional Overpower Relay

The BE1-32R Directional Overpower Relay and the BE1-32O/U Directional

Over/Underpower Relay are solid-state devices which provide versatility

and control in protecting machines against reverse power flow,

underpower and overpower conditions.

ADVANTAGES

Measures Real Power - El cos Θ.

Wide variety of input configurations are available including single-phase

and three phase, 3 and 4 wire systems.

Sensing ranges available from 0.5 to 6000 watts secondary.

Instantaneous, definite and inverse timing characteristics available.

Low input sensing and supply burdens.

Qualified to the requirements of

IEEE C37.90.1-1989 and IEC 255 for fast transient and surge

withstand capability;

IEC 255-5 for impulse.

UL recognized under Standard 508. UL File #E97033.

Five year warranty.

The BE1-32R Directional Overpower Relay and the BE1

32 O/U, Directional Over/Underpower Relays sense real

power flow (El cos Θ). These relays are solid-state

devices designed for use in single-phase or three-phase

systems to provide equipment protection for overpower

and/or underpower or to be used for supervisory control

of circuits. Both relay configurations may be used to

monitor either forward or reverse power. In the following

application examples, single-phase connections are

shown for simplicity.

APPLICATION EXAMPLES

The BE1-32 relays (R and O/U) are typically used in

applications where excessive power flow in the tripping

direction is indicative of undesirable situations. Typical

examples are discussed below. Notice: This product is

not recommended for power factors below 0.10. Contact

Basler Electric for recommended products.

EXAMPLE 1 - ANTI MOTORING

In this example, the power relay is used to protect the

prime mover rather than the generator. When an ac

generator, operating in parallel with a power system,

loses prime mover torque, it remains in synchronism

with the system and continues to run as a synchronous

motor drawing sufficient power from the system to drive

the prime mover. Sustained motoring can cause severe

damage to the prime mover. The Directional Power

Relay, with its wide sensitivity range, can detect levels of

reverse real power flow as low as 0.5 Watts secondary

and provide an alarm or trip the unit off line (See Figure

1). In this example, single phase sensing is usually

considered sufficient, since motoring is a balanced

condition.

EXAMPLE 2 - COGENERATOR CONTROL

Given that a co-generation system has automatic

engine controls, auto synchronizer, and automatic kW

and kVar controls, the system will virtually operate by

itself. The only functions not readily apparent are the

start/stop signals to the generators. Two system con

figurations using a Power Relay may be utilized to

generate contact closures for start and/or stop signals.

The first configuration (Figure 2) shows a power relay

connected to the utility to sense kW. The pickup point of

the relay is set at the maximum desired utility power

level. If the power relay contact closes, the generator

will be started and automatically paralleled with the

utility system. A time delay of 15 seconds or more is

generally included in the start circuit to ignore

transient overload conditions.