FAQs Archive | McGan Technology

Q: What are the causes of Pinholes?

While much care is taken in the handling of these probes they are still subjected to mechanical stress due to the sterilization methods or cleaning agents used, such as alcohol or glutaraldehyde. These mechanical stresses can produce pinholes, nicks or cracks in the protective insulation of the probe. Handling of the electrode surgical probe during the surgery may also cause damage to the insulation. There is also a possibility of defects caused to the probe during packaging or that may occur to it during or after being shipped from the manufacturer.

Q: On what principle does the McGan Integrity Testers operate?

The unit is a low frequency high voltage generator that delivers a stabilized preset DC output via a probe to an inspection electrode. As the electrode moves over the coating surface, if it encounters a pin hole or bare spot, a small current flows actuating a visible (non-hazardous) spark at the point of contact and a visible and audible alarm is activated in the unit.

Q: How is the applied voltage pre-set?

The voltage required is pre-set manually on the unit to a minimum level determined by the thickness of film of the coating product and its generic type i.e.: PVC, Teflon, FRP or polyethylene. Detailed instructions are set out in the section of the Operator’s Manual marked Recommended Minimum Voltage. It is important to follow these instructions in setting voltages as some surfaces have a much higher dielectric strength than others - consequently offering a high resistance to the conduction of electricity. Applied test voltages should only be sufficient to detect faults, otherwise overstressing of the dielectric strength may occur with possible surface rupturing.

Q: Does the Spark caused by locating the defect damage the insulation?

Since the test instrument found a defect it does not matter if the spark causes slightly more damage as the instrument should not be used. Note: The smaller the crack or pinhole in the insulation the more damage it may cause to the unintended tissue.