| 摘要 |
A protective grounding jumper cable tester is provided which includes a housing; a pair of jumper attachment terminals on the housing for attachment of a jumper cable therebetween; a dc voltage applying circuit disposed in the housing and connected to the pair of jumper attachment terminals for applying a direct current through a jumper cable attached between the jumper attachment terminals; and electronic means in the form of a PC board and microprocessor disposed in the housing and interconnected to the dc voltage circuit for applying a predetermined mathematical relationship to measure a resistance value of at least a portion of the jumper cable attached between the jumper attachment terminals. The electronic means in applying the predetermined mathematical relationship to measure the resistance value includes means for taking different voltage readings in accordance with kelvin's measurement procedure and calculating the resistance value from the voltage readings in accordance with kirchoff's current law.
|
