AEMC 3640 User Manual

Digital Ground Resistance Tester Model 3640 and 4610 29
4.6 Multiple Electrode System
Asingledrivengroundelectrodeisaneconomicalandsimplemeansof
makingagoodgroundsystem,butsometimesasinglerodwillnotprovide
sufcientlowresistance,andseveralgroundelectrodeswillbedrivenand
connectedinparallelbyacable.
Veryoftenwhentwo,threeorfourgroundelectrodesareused,theyare
driveninastraightline.Whenfourormoreareused,ahollowsquarecon-
gurationisusedandthegroundelectrodesarestillconnectedinparallel
andequallyspaced(Figure16).
Inmultipleelectrodesystems,the62%methodelectrodespacingmayno
longerbeapplieddirectly.Thedistanceoftheauxiliaryelectrodesisnow
basedonthemaximumgriddistance(e.g.,inasquare,thediagonal;ina
line,thetotallength).Asquarehavingasideof20 ftwillhaveadiagonal
ofapproximately28ft.
DIAGONAL
DIAGONAL
a
aa
a
Figure 16

AEMC 3640 Specifications

General

Brand	AEMC
Model	3640
Category	Test Equipment
Language	English