INSTRUCTION MANUAL
HIGH VOLTAGE INSULATION BREAKDOWN TESTER
5 KV AC, 5 KV DC, 100 m A
DOT – 458
A product of:
dot technologies
25, 2nd Floor, Victoria Road,
Bangalore-560047, Fax:08025542753
Phone:080 25549344 / 09844010308
Email :
INSTRUCTION MANUAL DOT – 458
INTRODUCTION:
DOT – 458 high voltage Insulation breakdown testers provides both AC voltage and pure DC voltages selectable on front panel. Dot 458 ranges from 0 to 5 KV AC, 0 to 5 KV DC with timer facility. DC voltage is rectified from AC using capacitor the ripple content is almost nil.
APPLICATION:
Useful for checking quality of insulation i.e. High Voltage with standing Capacity of Insulating Materials, Transformers, Components, Paper, Varnishes etc.,
CONTROLS, CONNECTORS, INDICATORS:
POWER ON:TURNS POWER ON/OFF (BY MCB)
HT ON LAMP:INDICATION FOR HT PRESENT
HT OFF LAMP:INDICATION FOR HT NOT PRESENT
TEST FAIL:INDICATION FOR INSULATION BREAKDOWN
TEST PASS:INDICATION FOR INSULATION PASSING THE TEST FOR
THE SPECIFIED DURATION
METER (KV):INDICATES THE VALUE IN KILO VOLT FOR
AC OR DC ACCORDINGLY
METER (mA):INDICATES THE VALUE IN mA FOR THE
LEAKAGE CURRENT THROUGH THE TEST PIECE
TRIPP CURRENT mA:FOR mA SETTING 0 TO 100 mA. THIS DECIDES THE
TRIPPING
TIMER:FOR SELECTION OF TIMER FROM 0 TO 5 MIN.
ZERO POSITION SIGNIFIES TIMER IS OFF.
OUTPUT:TO SELECT AC OR DC OUTPUT
OUTPUT ON:RED SWITCH FOR ENABLING HT ON. IF THE TIMER
IS SELECTED THEN TIMER WILL GO ON BY THIS SWITCH
RESET:BLACK SWITCH TO RESET OR MAKE HT OFF
OUTPUT:OUTPUT SOCKETS FOR AC AND DC VOLTAGE
TIMER ON:TIMER CAN BE SELECTED BY DEPRESSING THIS
SWITCH OTHERWISE THE UNIT WILL BE MANUALLY HT
ON AND HT OFF.
ZERO START:BY DEPRESSING THIS SWITCH THE HT VOLTAGE ONCE
TRIPS CAN BE MADE ON ONLY IF THE VARIAC/VOLTAGE VARIABLE KNOB IS BROUGHT DOWN TO MIN / ZERO POSITION.
BUZZER ON:BY DEPRESSSING THIS SWITCH , THE BUZZER WILL GO
ON WHEN HT IS ON
HT WARN LAMP:AN ADDITIONAL LAMP FOR HT ON CAN BE CONNECTED
THROUGH REAR TERMINATIONS BY DEPRESSING THIS
SWITCH. (POTENTIAL FREE CONTACTS ARE PROVIDED.)
FOOT SWITCH:FOOT OPERATED SWITCH FOR HT ON CAN BE
CONNECTED THROUGH REAR TERMINATION BY
DEPRESSING THIS SWITCH.
MAIN SOCKET (R):POWER INLET 230 V AC, AND FUSE.
HT PROBE:PROBE TO BE INSERTED TO HT SOCKET THE OTHER
END SHOULD BE USED FOR HT OUTPUT. PROBES ARE
INSULATED FOR 20 KV.
INSTALLATION:
* Check instrument physically, if damaged return back to factory Within 15 days of receipt.
* Connect power to 230 V AC three pin supply.
* Press power on switch to on position.
* Keep voltage KV knob to minimum value and mA knob to required value or middle value
i.e.50 m A.
* Connect HT RED probe to output AC or DC as desired and black probe to middle GND
terminal.
* Switch HT on and off for three four times and check if HT is getting on, now off / reset HT
Voltage.
* Select AC or DC by output select.
* If timer is required – depress timer on switch and select time also.
* Select zero start / buzzer if required.
* Connect test probe across the test piece; make HT on rotate voltage knob to clockwise
direction to the required voltage.
* Timer will go off after the selected time lapse and the test pass lamp will glow if the test piece
is good, or fail lamp will glow if the test piece is bad.
* Test fail lamp glows only when more current passes through the test piece (from selected
mA value).
* mA indication will be seen only if the current passing through the piece is higher than
0.2 mA.
SAFETY REGULATIONS:
* External voltage should not be applied on test terminals.
* Don’t touch the tip of HT probe while HT is on.
* HT probe should not be kept nearer to conductive material.
* Three-pin cord must be used with grounding terminal for line voltage.
LIMITATIONS:
* Not recommended for application where more leakage current testing to be carried out.