MODEL : OLDRDT

This product is a motor protection system that safeguards the Single Phase Motor against Overload, Dry Run and Single Phasing. This product has to be attached to the existing motor starter. It allows the motor load to pass through it. The current drawn by the motor is continuously monitored and displayed on the LCD. The low current and high current settings need to be adjusted by the user. The motor is turned OFF in case of over current, under current (dry run) and when any of the supply phases are absent thus protecting the motor from damages. The reason for the trip along with the tripping current is displayed on the LCD. The device also offers an OFF timer which the user can set to turn OFF the motor automatically after the set time is complete.

Maximum Current Range:

1 to 3HP: 30A
1 to 5HP : 50A

Connections:

Connect the incoming power supply lines 220V (Auxiliary supply) to connector 1 and 2 (red and black respectively)
Connect connectors 3 and 4 (green and yellow) in series with the No- Volt coil or in series with the holding contact of the Contactor
Pass the load wire through the CT hole provided

Operations:

Normally Closed Configuration

The LCD powers up automatically when the supply voltage is given. C1 and C2 (green and yellow relay contacts) (Normally closed) will remain closed till current is within the set limit. The relay contacts open only during the faulty conditions or when the motor is switched off manually for 5 seconds. The reason for the trip is displayed on the LCD.

Normally Open Configuration:

The LCD powers up automatically when the supply voltage is given. On sensing the current in the CT (wire passed through the tubes), C1 and C2 (green and yellow relay contacts) (Normally open contact) will close. C1 and C2 will remain closed till current is within the set limit. C1 and C2 open only during the faulty conditions or when the motor is switched off manually. The reason for the trip is displayed on the LCD.

Technical Specifications:

Dry Relay Contacts
Wire Size to be used for L1, L2 and C1, C2 is a minimum of 0.5 sq. mm

Tripping time:

Overload - 12 seconds
Dry Run (Underload) - 8 seconds

Setting:

Turn the Overload [H( )] [green knob] to maximum (clockwise)
Turn the Dry Run [L( )] [Blue knob] to minimum (anticlockwise)
Turn ON the motor and observe the load current in the second line of the LCD
Set the Overload H( ) value to 2 points more than the load current by rotating and observing the change in H( ) value in the first line of the LCD.
Set the Dry Run L( ) value to 2 points less than the load current by rotating and observing the change in L( ) value in the first line of the LCD.
Motor OFF Timer is the first knob. If the timer is not required, turn it completely towards the left hand side.
If the OFF timer needs to be set, turn the white knob on the right hand side to increase the time which can be seen on the far right inside the brackets on the second line of the LCD
The numbers appearing next to the current reading outside the brackets are the time elapsed.
Note: Set the L( ) value to minimum if the Dry Run Protection is not required.

Application:

Naren Overload Dry Run Relay is used in all Single Phase Submersible Starters as a protection mechanism to protect the motor against current and voltage irregularities. This device effectively switches OFF the motor in any irregularity and hence prevents burning of the motor windings. The reason for turning OFF is displayed on the LCD which makes the diagnosis easy. This device is rugged and is specifically designed for agricultural operations. The motor safeguarding devices like these are very critical which will save the users from the costs incurred due to motor failures.

WARRANTY:

This product carries a warranty of 6 months from the date of purchase. Any issues within the warranty period will be attended to free of cost at our works in Bangalore. Post the warranty period, the product will be eligible for the paid service at our works. The invoice copy acts as a warranty card. The shipping of the product for repair will have to be done by the consumer.