What is the difference between a Ground Continuity test and a Ground Bond test?
	Is a Ground Bond test required for 100% production line testing?
	What is the maximum ground circuit impedance allowable during a Ground Bond test?
	What is the "Kelvin Method" of measurement?
	How long should a Ground Bond test be performed?

Q.	What is the difference between a Ground Continuity test and a Ground Bond test?
A.	A Ground Continuity test is performed on the third pin ground of a line cord-terminated product. The test verifies that the safety ground is present in the system yet it does not test the ability of the safety ground to withstand any fault current. The Ground Bond test is performed in a similar fashion but also verifies that a product’s safety ground can adequately handle any fault current due to an insulation failure. Top
Q.	Is a Ground Bond test required for 100% production line testing?
A.	This depends on the standard. The Ground Bond test is most often found as a type test but can also be specified as a 100% production line test. Contact your local safety agency office or our Technical Services department for more information. Top
Q.	What is the maximum ground circuit impedance allowable during a Ground Bond test?
A.	The maximum impedance of the ground circuit is dependent upon how the DUT’s input power and safety ground are terminated: terminal block, line cord, etc. The maximum impedance may vary depending on the specification you are testing to but the most common values are 0.1 - 0.2 Ω. Contact your local safety agency office or our Technical Services department for more information. Top
Q.	What is the "Kelvin Method" of measurement?
A.	This is a standard four wire measurement method used during a Ground Bond test to eliminate the inherent test lead resistance from the test results. The Kelvin Method provides more accurate resistance measurements which are crucial when dealing with the miniscule resistance values measured during a Ground Bond test. Top
Q.	How long should a Ground Bond test be performed?
A.	The test time may or may not be specified in some performance specifications and can be as high as 120 seconds. Production line tests may only call for a Ground Continuity test not a Ground Bond test. Contact your local safety agency office or our Technical Services department for more information. Top