Digital Insulation Tester
1. SPECIFICATIONS
1.1 General Specifications
Display: 3½ digit liquid crystal display (LCD) 20mm height with a maximum reading of
1999.
Over range Indication: (1) or (-1) is displayed at MSD
Low Battery: Displayed when the battery voltage drops is Low.
Safety standard: Meets the requirement of IEC 1010 for installation category II, 1000V
phase
to earth.
Measurement rate: 2.5 measurements per second.
Operating condition: 0°C to + 50°C, 0-75% RH
Storage conditions: -20°C to + 60°C, 0-80% RH with battery removed.
Accuracy: + (3% rdg + 2dgt ) Accuracy specifications at 23 + 5°C, less than 75% RH.
Power Supply: 9 volts (6 x 1.5V) battery, Eveready type 1015 or equivalent. OR Power
Adaptor 9V, 1.5 A
Dimensions: 139 x 99 x 54mm (approx)
Weight: 395gms including battery, Eveready type 1015 or equivalent.
Accessories: Test leads (pair) X 1, 1.5V battery (installed) X carrying case X 1.
Dielectric Strength: 3.5kV @ 50Hz for 1 min. between input terminals and case.
Insulation Resistance:
More than 50MΩ at 500V between circuit and case
.
1.2 Electrical Specifications
Accuracies are +(% reading plus number of digits) at 23 +
5°C, and humidity of less than 75% RH
Model NO
DIT90A
DIT90B
DIT90C
DIT90D
DIT90E
Rated Voltage
1000V
1000V
500V
500V
Range
2000MΩ
200MΩ
2
000MΩ
200MΩ
Resolution
1
MΩ
0.1
MΩ
1
MΩ
0.1
MΩ
Max. No. load
Voltage
+25% of rated voltage
Short Circuit
Current
Accuracy
<2 mA
+ (3%rdg + 2dgt)
2. SAFETY INFORMATION
1. The circuit under test must be de energized and isolated before connections are made.
2. Circuit connections must not be touched during a test.
3. After insulation tests capacitive circuits must be allowed to be discharged.
4. Test leads must be in good order, clean and have no cracked or broken insulation.
5. Do not push the test button before all connections and preparations are done. The instrument
must only be used by suitable trained and competent persons.
Warning and safety symbols
Caution refer to this manual before using the meter.
Dangerous
voltages.
C€ Comply with IEC1010 –
1.
3. OPERATION
Before taking any measurements, ready the safety information section. Always
examine the instrument for Range, contamination (excessive dirt, grease, etc.)
and defects Examine the teat leads for cracks or frayed insulation. If any abnormal
conditions exist do not make measurements.
3.1 PRECAUTIONS
1. Disconnect all power from the circuit under test when making measurements. If any voltage is
present in the test circuit an erroneous reading will result.
2. When the test switch is pressed a high voltage is generated between ‘
L
’ and ‘
E
’ terminals. Do not
touch any live parts in the circuit during measurement.
3.2 INSULATION RESISTANCE MEASUREMENT
1. Connect red test lead to ‘
L
’ Terminal
2. Connect black test lead to ‘
E
‘ Terminal
3. Short the red and black test lead and press t
he test switch, Zero MΩ should be indicated on the
display.
4. Connect the test leads to circuit under test and press test switch.
5. Display indicates the reading in MΩ, if insulation resistance is higher than the instrument, ‘1’ or ‘
-
1’ is
indicated.
4. MAINTENANCE
If there appears to be a malfunction during the operation of the meter. The
following steps should be performed in order to isolate the cause of the problem.
1. Check the battery.