Dc And Ac Current Measurem Ent; The M Easured Value Show S On The Display - Digimaster DM-58 A Manual De Uso

B. DC and AC Curre nt Mea sure ment
Warning – Ne ver a tt e mpt an in- circuit current m ea sure ment wher e th e open circuit volt age
bet ween t erminals and ground is gr eat er th an 250 V. If the fus e burns ou t during
me a sure ment, the Me ter may be d a maged or the oper ator him self m ay b e hurt.
Use pro per term inals, f unctio n, an d r ange for the measur ement. Whe n the testin g lea ds ar e co nn ecte d to the
curr ent te rmi nals, do not par allel them ac ross any circuit.
The DC Cur rent rang er are:
Mod el D M5 8A/: 2 0µA, 2 mA, 2 0m A, 2 00 mA an d 2 0A.
Mod el D M5 8B: 2 mA, 20 0mA and 20 A.
The AC Cu rr ent r an ges are:
2mA, 20 0mA and 20 A.
To measure curr ent, do the f ollo wing:
11. Tur n off po wer t o the ci rcuit. Disc ha rg e al l hi gh-v oltag e ca pacitors.
12. Insert t he r ed test l e ad into A o r µ AmA (DM58A ) or mA (/D M58 B) te rmi nal a nd the black test le ad i nto
the CO M ter mi nal.
13. Set the rot ary switc h to a n a ppr o pri ate m eas urem ent position i n A
14. Br eak th e c urrent pat h to be test ed. Con n ect the red test l ea d to the mor e p ositiv e si de of the br eak and
the black test le a d to the mor e n egative side of the br eak.
15. Tur n on po wer t o the ci rcuit.
The measur ed v al ue sho ws on th e displ ay.
:
Note
If the v alue of curre nt to be meas ure d is unk nown, us e th e maxim um measur ement p ositi on, a nd reduce
l
the r an ge ste p by step u ntil a satisf actory rea din g is o btai ned.
For saf ety sake, the me as uri ng time f or hig h cu rrent ( >10A) s ho ul d be l ess tha n 10 s econds a nd the
l
interval time bet ween 2 meas ur eme nts sh oul d b e gre ater tha n 1 5 min utes.
When curre nt m easurem ent has be en co mp let ed, discon nect the co nnecti on bet we en th e t estin g l ea ds
l
and the circuit un de r test.
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black
red
or A ran ge.