GHM Delta OHM HD2304.0, Руководство по эксплуатации

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HD2304
- 11 -
V1.8
PROBES AN D M EASUREM EN TS
The inst rum ent m easures absolut e, relat iv e and different ial pressure using t he PP471
SI CRAM m odule and t he TP704 and TP705 series probes. I t also m easures t he
t em perat ure wit h a Pt 100 sensor wit h SI CRAM m odule or wit h direct 4 w ire Pt 100
probes.
The SI CRAM m odule act s as an int erface bet ween t he sensor on t he probe and t he
inst rum ent . There is a m icroprocessor circuit w it h a perm anent m em ory inside t he
m odule t hat enables t he inst rum ent t o recognize t he t ype of pr obe connect ed and t o
read it s calibrat ion inform at ion.
Th e pr obe s a r e de t e ct e d du r in g t ur n on , a n d t h is ca n n ot be pe r for m e d w h e n
t h e in st r u m e n t is a lr e a dy on , t h e r e for e if a pr obe is conn e ct e d a n d t h e
in st r u m e n t is on , it is n e ce ssa r y t o t ur n it off a n d on
.
The probes fit t ed wit h SI CRAM m odule are calibrat ed in t he fact ory; no calibrat ion is
required by t he user.
PP4 7 1
M OD U LE FOR PRESSURE M EASUREM EN T
The PP471 m odule act s as an int erface bet ween t he TP704 and TP705 series Delt a
OHM probes and t he inst rum ent . The
TP7 0 4
ser ies pressure probes have a 1/ 4" BSP
t hreaded m ale connect ion, and m ust be screwed int o t he syst em using t he necessary
sealing gasket s. The
TP7 0 5 series have t wo Ø5 connect ions w here t he suit able t ubes
are insert ed in order t o perform t he desired m easurem ent .
Ca u t ion ! Please pay careful at t ent ion t o t he j oint pressure sealing; use suit able
gasket s and j oint s. The t hreaded connect ion is prot ect ed by a plast ic cap. Put it back
aft er use as it prot ect s t he pressure cell from foreign bodies.
I M PORTAN T! Ensure t he pr obe 's bot t om sca le is highe r t ha n t he pr e ssur e t hat
w ill be m e a sur e d. I n ca se t his v a lu e is unk now n, st a r t by using highe r -
ca pa cit y pr obe s.
For e ve r y pr e ssur e pr obe a r a nge of ove r loa d pr e ssur e a nd a bur st pr e ssur e
a r e de cla r e d: pr e ssur es in t he r a nge of ove r loa d pr e ssur e don’t ca use t he
br ea k of t he se nsor but t he de cla r e d a ccur a cy ca n be over com e . Pr e ssur e ove r
t he st a t e d bur st pr e ssur e m a y br e a k t he se nsor . The applica t ion of highe r
pr e ssur e s t ha n t he ove r loa d pr e ssur e lim it , a lt hough low e r t ha n t he bur st
pr essur e, m a y pr oduce pe r m a nent da m a ge t o t he pr obe ( e .g. offse t shift ) .
N ever ex cee d t he st a t e d bur st pr e ssure ( se e Te chnica l Cha r a ct e r ist ics of t he
pr obe s a t pa ge x x )
Upon t urning on t he inst rum ent aut om at ically det ect s t he PP471 m odule. The probe's
t ype ( absolut e, relat ive or different ial) and bot t om scale value are det ect ed even
when t he inst rum ent is on ( see chapt er 3) .
To change t he inst ant aneous or peak value unit of m easurem ent , press UNI T. The
follow ing unit s of m easurem ent are available:
Pa, hPa, kPa, m bar , bar, at m , m m Hg, m m H
2
O, kgf/ cm
2
, PSI , inchHg, inchH
2
O.
Som e unit s of m easurem ent require a degr ee of m ult iplicat ion:
•
t he " - 3" sym bol indicat es t he displayed value m ust be div ided by 1,000;
•
t he " 3" and " 6" sy m bols indicat e t he displayed value m ust be m ult iplied
respect ively by 1,000 or by 1,000,000.
The inst rum ent does not aut om at ically det ect t he probes which are not fit t ed w it h
SI CRAM m odule.