Leakage Current Testers
GAOTek Leakage Current Tester measures the undesirable leakage current that flows through or across the surface of the insulation or the dielectric of a capacitor. This test is generally carried out at 100%-110% of the rated input voltage of the product under test. The maximum acceptable limit of a leakage current is generally 210 micro amperes. At first, this test was mandatory for medical devices only. Leakage current can be an indicator of the effectiveness of insulation on conductors. High levels of leakage current may be present in circuits where electronic equipment with filters is used, and can cause voltages that disrupt normal operation of equipment. It is possible to locate the source of leakage current by using a low current leakage current clamp to take methodical measurements as described above. If necessary, this enables you to re-distribute loads around the installation in a more balanced way.
Importance of Leakage Current:
Electrical equipment commonly includes a grounding system to provide protection against a shock hazard if there is an insulation failure. The grounding system usually consists of a grounding conductor that bonds the equipment to the service ground (earth). If there is a catastrophic failure of the insulation between the hot (power) line and touchable conductive parts, the voltage is shunted to ground. The resulting current flow will cause a fuse to blow or open a circuit breaker; preventing a shock hazard. Obviously, a possible shock hazard exists if the grounding connection is interrupted, either intentionally or accidentally. The shock hazard may be greater than supposed because of the leakage currents. Even if there is no insulation failure, interruption of the leakage currents flowing through the ground conductor could pose a shock hazard to someone touching the ungrounded equipment and ground (or other grounded equipment) at the same time. This possibility is of much more concern in medical applications, where a patient may be the recipient of the shock. A fatal shock could result if the patient is in a weakened condition or unconscious, or if the leakage current is applied to internal organs through patient contacts. The double insulation provided in non-grounded equipment provides protection by using two separate layers of insulation. The protection in this case is ensured because both layers of insulation are unlikely to fail. However, the conditions that produce leakage currents are still present, and must be considered.
The causes of leakage current:
Insulation has both electrical resistance and capacitance – and it conducts current through both paths. Given the high resistance of insulation, very little current should actually leak. But — if the insulation is old or damaged, the resistance is lower and substantial current may flow. Additionally, longer conductors have a higher capacitance, causing more leakage current. That’s why GFCI breaker manufacturers recommend one-way feeder length be limited to 250 feet, maximum.
Electronic equipment, meanwhile, contains filters designed to protect against voltage surges and other disruptions. These filters typically have capacitors on the input, which adds to the overall capacitance of the wiring system and the overall level of leakage current.
GAOTek Leakage Current Tester uses following technologies
• Test device for earth leakage current and touch current
• Measurement circuit (according to European standards)
• Internal, potential-free source for the DUT supply
• Secondary-side detection of current and voltage
Measurement of Leakage Current to Ground
When the load is connected (switched on), the leakage current measured includes leakage in load equipment. If the leakage is acceptably low with the load connected, then circuit wiring leakage is even lower. If circuit wiring leakage alone is required, disconnect (switch off) the load.
Test single-phase circuits by clamping the phase and neutral conductor. The measured value will be any current flowing to ground.
Test three-phase circuits by clamping around all three-phase conductors. If a neutral is present, it should be clamped along with the phase conductors. The measured value will be any current flowing to ground.
Measuring leakage current through the ground conductor
To measure the total leakage flowing to the intended ground connection, place the clamp around the ground conductor.
Measuring leakage current to ground via unintentional paths to ground.
Clamping phase/neutral/ground together identifies imbalance current that represents leakage at an outlet or electrical panel via unintentional paths to ground (such as the panel sitting on a concrete base). If other electrical bonding connections exist (such as a connection to a water pipe), a similar imbalance may result.
GAOTek Leakage Current Tester has following features
· True RMS Readings
· Reads in Measurement Indication Units (MIU) up to .005 MIU
· Output Allows Measurement of Peak Current in Non-Sinusoidal Wave Forms
· Let-Go, Reaction, and Burn Hazard Response Networks
· Detects dangerous AC & DC Leakage currents
· Includes Test Leads, Alligator Clips, Batteries and Manual
· Measurement of leakage current with 3 mA range and 1 µA of resolution, for accurate monitoring of insulation erosion
· Broad range of measurement, from 1 µA up to 60 A, for all installation needs
· Advanced shielding to ensure accurate results when measuring near other conductors
· The high durability clamp construction can withstand over 50,000 operations, added ruggedness that extends the life of your leakage clamp.
· Easy-to-carry, pocket-sized leakage current tester with wide 40 mm (1.5 in) jaw size
· Handy “Display-Hold” button for capturing leakage current readings in hard-to-reach places
· Auto power-off, with warning buzzer, saves battery life
· Conformance to IEC1010 and EMC standard for confident measurements
· Meets all of the applications and performance classes in safety standard VDE0404-4 and VDE0702 for leakage current and differential current measurement of electrical appliances
· Measurement of Leakage Current to Ground
· Measuring leakage current through the ground conductor
· Measuring leakage current to ground via unintentional paths to ground.
· Dielectric breakdown Test.
· Dielectric Withstand Test
Showing all 2 results