Ac Current Measurement - Digimaster DM38A Manual De Empleo

D. AC Curr ent Mea sure ment
Warning – Nev er at tempt an in- circuit curren t me asur ement wh ere the volt age b et ween ter minals and
round is greater th an 6 0 V or 30 V rm s.
If the fus e burn s out during m easurem ent, the Met er ma y be da m ag ed or th e op erator himself may be
hurt. Dis connect po wer supply b efor e m aking me asur e men t. Use proper ter min als, function, and
range for the m ea sure men t. W hen the te sting lea ds are con ne cted to the curren t ter minals, do not
parallel the m a cros s an y circui t.
To measu re c urr ent, d o th e f ollo wi ng:
11. Tur n off power t o the ci rcuit. Disc harg e al l hi gh-v oltag e ca pacit ors.
12. Insert th e r ed test l ea d int o th e m A or 20 A t ermin al o r 10 A ter min al an d th e bl ack test lead into the CO M t ermi n al.
When m eas uri ng c urrent at 20 0mA be lo w, i nsert th e re d test lead into m A t ermin al while me asur ing cur rent
200m A or ab ov e, inse rt the r ed test l ead into 1 0A or 20 A t erm inal.
13. Set the rotary switch to a n a ppr o pri ate m eas ur em ent p ositi on i n A
14. Break th e cu rrent path t o be teste d. Conn ect the red test l ea d to th e m or e positiv e sid e of the b re ak a nd t he bl ack
test lea d to th e more ne gativ e sid e of the br eak.
15. Tur n on power t o the ci rcuit.
The measur ed v alue sho ws on th e dis pl ay .
Note
If the v alue of current to b e me as ured is u nkn o wn, us e th e maxi mum me asur em ent p ositi on ( 20 A) an d 20 A
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termi na l or ( 10A) an d 10 A te rmi nal, and re duc e th e ra ng e ste p by step until a s atisf actory read ing is o btai ne d.
Rep lace appr opri ate r atin g f use when th e fuse is burnt.
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Fuse specif icatio n: 0.31 5A. 2 50V fast ty pe f use, Ø 5 x 20 mm.
DM3 9A/ – At 10 A R ang e: For c onti nu ous me asu reme nt < 10 sec onds and i nte rv al not less tha n 1 5 mi nut es.
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DM3 9B– At 2 0A Ra nge: Fo r co ntinuo us measur ement < 10 s eco nds and int erval not less than 15 min utes.
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When cu rrent m eas urement has bee n compl ete d, disco n nect the c on nectio n bet we en th e testin g le a ds and the
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circuit u n der t est.
. rang e.