Category: Basler Electric

Basler Electric offers a high powered, low-cost digital excitation control system,

the DECS-100. This environmentally rugged product is ideally suited for

controlling the output of brushless excited synchronous generators up to 5MW.

The DECS-100 has a very impressive 7Adc output from a pulse width modulated

power stage. The DECS-100 is perfect for machines that will be paralleled to other

generators and/or to the utility system. It is ideal for distributed generation,

co-generation and peak shaving applications. 

The DECS-100 is easy to use, and it has communications capability with a PC.

The DECS-100 utilizes microprocessor technology and control algorithms pioneered

by Basler Electric for longer than a decade. It shares many features and functions

of our larger excitation control systems.

The DECS-100 is Basler Electric’s fifth generation of microprocessor-based excitation

system.

The DECS-100 is perfect for paralleling applications where generator to generator

and/or generator to utility paralleling occurs with VAR/PF control and Over- and

Underexcitation Limiting. The DECS-100 offers high functionality,communications,

and performance at an extremely affordable price. The DECS-100 is very rugged and

offers an extremely robust mechanical design that is cURus recognized, CE compliant,

and DNV certified.

Provides economical high-speed protection in a conventional package

for high-impedance differential applications.

Product Features & Benefits

• Proven high-impedance differential provides optimum speed and selectivity.

• Space and cost-saving configurations available featuring a single-phase S1

case, a three-phase M1 case, and a three-phase 19″ rack-mount case.

• Easily verify external wiring and prevent misoperation with the CT Circuit

Diagnostic function and Steady-State Unbalance alarm.

• Two timing options are available. Each includes a jumper-selectable

instantaneous or intentional time delay.

• Timing Option A1: The instantaneous jumper position provides fastest tripping.

The 20 millisecond intentional delay jumper position prevents tripping for short

duration faults within the zone of protection that is protected by a high speed fuse.

• Timing Option A2: The instantaneous jumper position provides fastest tripping.

The 2 millisecond intentional delay jumper position prevents nuisance tripping for

very short duration faults such as nearby lightning strikes.

• Reduced battery load with low burden power supply.

• Easily perform in-case system and device tests using test paddles.

• Available as a plug-n-play retrofit for GE PVD21B or PVD21D differential voltage

relays. Fits into an existing M1 GE PVD case. Request Basler part number 9282300111.

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.

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.

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:

The Electronic Manual Voltage Control MVC-300 allows a generator’s output

voltage to be controlled manually by a potentiometer or automatically by a

voltage regulator. It is used as a back-up system for the automatic voltage

regulator. The unit can be mounted on a control panel in ground vehicles,

stationary equipment or shipboard locations.

FEATURES:

• Designed to operate with all Basler voltage regulators rated

at 7 amperes continuous and below

• Completely solid state

• 120-240 Vac operation

• Multiple field output ratings

• Automatic voltage build-up circuit

• Small and light for easy panel or door mounting

• CSA approved/UL recognized

• Available from stock

The Electronic Manual Voltage Control MVC-300 is a solid-state device en

closed by a wrap-around metal chassis. The MVC-300 is for mounting through

a panel with controls accessible from the front of the panel or can be mounted

behind the panel. A terminal strip located on the rear of the device facilitates

installation. A manual voltage adjust potentiometer and a manual-off-auto

switch are provided on the front face of the unit. For use of a user-supplied

external manual adjust potentiometer or for adjust by a motor operated control

(MOC), order MVC-301. The MVC-300 and MVC-301 are designed to operate

with Basler voltage regulators powered from 120 or 240 volt AC sources up to

320 Hz. The adjustable output of the MVC-300 supplies power to 32. 63 or 125

volt fields at 7 amps.

Load Current Approaches Fault Current

Pickup settings on a phase overcurrent device are normally set below the expected fault current levels on

that line by some margin. Consequently, it is possible for load current to approach (or exceed) the pickup

setting on the relay. This could lead to an undesirable trip for an acceptable load condition.

Weak Infeed Condition

During a period of abnormally low system voltage, leading power factor current above relay pickup can

flow in the non-trip direction of a line. Probable current sources are outlying capacitor banks. This could

cause the current to be sensed as lagging current flowing in the trip direction and leading to an

undesirable trip. (A condition often referred to as weak infeed because the lower voltage system – where

load is present – attempts to correct the undervoltage condition on the higher voltage system.)

Application

Without the ability to act on the direction of current flow, it is difficult to coordinate the settings of time

overcurrent relays on lines that interconnect a series of substations. Without this capability, either

undesired tripping of adjacent lines may occur or a fault may go undetected because of the high settings

required by non-directional relays.

With directional time overcurrent relays, the settings and time delays can be decreased and the undesired

tripping eliminated. Figure 1-5 illustrates the use of directional overcurrent relays on a group of

interconnected distribution substations fed from a common source. In this example, non-directional

overcurrent relays (51) are used to protect the lines leaving the supply bus because there is only one

source of fault current. However, the breakers at the load buses (C, D, E, and F) are protected by

directional time overcurrent relays (67) to prevent overtripping in the event of a fault. This will remove the

faulted line and retain service to the connected loads.

In the case where two sources of power can supply fault current, as shown in Figure 1-6. directional

overcurrent relays will need to be applied to each end of the protected lines to prevent undesired tripping.

If the supply to the protected portion of the system is constant, and if the magnitude of the fault current is

determined primarily by the location of the fault on the line, the selection of a more inverse time

characteristic is more desirable to provide selective coordination with adjacent line protection. However, if

the capacity of the supply varies significantly over a period (such as a day), a less inverse time or even

the definite time characteristic, may be preferred to provide smoother coordination.

Limited Region of Operation

A limited region-of-operation option is available to provide additional protection against false tripping on

mutually coupled lines. Faults on adjacent lines that share the same poles, towers, or right-of-way may

induce currents on the protected line which appear as fault currents in the tripping direction. The limited

region of operation mode provides discrimination between faults on the protected line and faults on the

adjacent line. To order this option, specify option 3-5 or 3-6.

One consideration in applying a phase directional overcurrent relay is the definition of trip direction. For

most applications, the setting of the relay directional element is based upon the impedance characteristics

of a given circuit. This angle is then used as the maximum torque angle and any current flowing in the

half-plane defined by this angle is considered to be in the trip direction.

However, there are at least two situations where the half-plane trip region is not adequate. They are when

load current approaches the fault current and when leading current flows in the non-trip direction above

the relay pickup setting.