P O U 3

Application
Pradeep's Under & Over Voltage Relay - Model P-O/U 3 , has wide range industrial application for protection  against problems of under and over voltage in 1 _ applications. It has settable limits for under and over  voltage conditions beyond which connected load will be cut off thru' relay along with alarm indication. The  unit can be set for manual or automatic mode of operation. This unit is ideal for D.G. set application. Housed  in 96mm X 96mm sq. enclosure, the unit uses state of the art technology.

Typical applications for this unit are

Seven segment LED display is provided for indication of settings and actual conditions

Principle of operation
Pradeep's under & over Voltage Relays are designed using basic principle of precise sensing of actual voltage  w.r.to pre-set levels of permissible under & over voltage. In the event of actual voltage outside the pre-set  range, along with LED indication of FAULT condition, the relays will operate to activate protection circuit.  Common alarm is activated for under voltage or over voltage conditions, where as protection circuits are  activated for individual conditions. With the help of state of the art microprocessor based electronic circuitry, accurate control over the entire range is achieved. (Details provided in specifications).

Salient Features
The microprocessor based under & over voltage relay, model) is distinguished for its features, construction,  operation and cost effectiveness. The versatility of this model is a result of careful consideration and  understanding of the wide spectrum of the user needs and convenience, whether during testing or online  operation.This instrument is designed using state of the art Integrated Circuits (IC), and glass epoxy Printed  Circuit Boards (PCB). It is easy to configure this instrument, as the same is very user friendly. The instrument  incorporates a stabilized power supply and filter circuit for absorbing power supply transients, thus ensuring  accurate control / and a stable display. The output is displayed prominently and has a viewing distance of  more than 4 meter.

BURN-IN
Each instrument is tested and aged at ambient conditions for 48 hours in electrically energized  condition prior to delivery as per Pradeep's norms for verification of design reliability. This practice ensures  the unit's continued performance to specifications and to customer's satisfaction.

Type Tests: models are type tested at ERTL (West), STQC,
Govt. Of India for following:

Additional important features

Technical Specifications

• Input voltage
    110 V ac (Optional - 240 V ac)
 • Under voltage range
    88 V - 110 V ac (Optional 192V - 240 V ac)
 • Over voltage range
    110 V - 132 V ac (Optional 240V - 288 V ac)
 • Resolution (setting)
    1 volt over the entire range
 • Accuracy Display
    Seven segment RED LED digit display for voltage. (Actual voltage during normal operation. Set point      while setting)
 • Additional Indications
    a) Red LED to indicate Power ON
    b) Green LED relay operation
    c) Orange LED for under & over voltage setting.
    d) Blue LED for common relay operation. (Indication for one of the fault or both fault condition).
    e) Red LED for AUTO reset operation.

Electrical Specifications

• Mains Supply
    90 V to 260 V AC/DC Voltage
 • Output
    3 pair N/O ,N/C contacts - 3 relays. One each for under & over voltage conditions and one common     output for both conditions.
 • Relay Contact Rating
    5 A at 240 VAC Res. Load, 100 W at 220 VDC.
 • Terminals
    Screw Caged, suitable for 0.2sq. mm. - 4 sq. mm. Solid Conductors
 • Insulation
    Insulation resistance >=100 M ohms at 500 V DC between each Terminal with earth
    Voltage proof between all mains supply terminals shorted together & earth-No breakdown for one     minute.
    - Factory tested at 1.5 kV rms, 50 Hz.
    - Subsequent field test at 0.5 kV rms, 50 Hz
 • Power Consumption
    10 VA max.
 • Operating Conditions
    Ambient temp. range. (-) 25°c. to 60°c.

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