M-system RB Instruction Manual - page 4
RB/RBS
P. 4 / 4
EM-1334 Rev.7
5-2-55, Minamitsumori, Nishinari-ku, Osaka 557-0063 JAPAN
Phone: +81(6)6659-8201 Fax: +81(6)6659-8510 E-mail: info@m-system.co.jp
SIMPLE LOOP TEST OUTPUT
Option /E2
Simulated0%and100%outputisavailablewithOption/E2.
SwitchtheLoopTestSelectorpositions.
Topposition: 0%fixed
Middleposition:100%fixed
Bottomposition:Cancelthelooptestmode
(Back to the normal operating mode)
CHECKING
1) Terminalwiring:Checkthatallcablesarecorrectlycon-
nected according to the connection diagram.
2) Powerinputvoltage:Checkvoltageacrosstheterminal
7–8withamultimeter.
3) Input: Check voltage across the terminal 3 – 4 with a
sensitive voltmeter.
(With20°Cor68°F,approx.220mVwithPt100,approx.
110mVwithPt50Ω.)
IfRTDwiresarebroken,theoutputgoesover100%(be-
low0%withdownscaleprotection)duetoburnoutpro-
tection function. Check leadwires in such a case.
4) Output: Check that the load resistance meets the de-
scribed specifications.
ADJUSTMENT PROCEDURE
This unit is calibrated at the factory to meet the ordered
specifications, therefore you usually do not need any cali-
bration.
Theoutputsignalcanbefinelyadjustedtomatchittoare-
ceiving instrument, or to compensate input wire resistance
whentheunitiscombinedwithazenorbarrier.Followthe
regularcalibrationprocedureexplainedbelow:
■
HOW TO CALIBRATE THE OUTPUT SIGNAL
Useasignalsourceandmeasuringinstrumentsofsufficient
accuracy level. Turn the power supply on and warm up for
morethan10minutes.
1) ZERO:Apply0%inputandadjustoutputto0%.
2) SPAN:Apply100%inputandadjustoutputto100%.
3) CheckZEROadjustmentagainwith0%input.
4) When ZERO value is changed, repeat the above proce-
dure1)–3).
MAINTENANCE
Regularcalibrationprocedureisexplainedbelow:
■
CALIBRATION
Warmuptheunitforatleast10minutes.Apply0%,25%,
50%, 75% and 100% input signal. Check that the output
signal for the respective input signal remains within the
range of accuracy described in the data sheet. When the
output is out of tolerance, recalibrate the unit according to
the“ADJUSTMENTPROCEDURE”explainedearlier.
LIGHTNING SURGE PROTECTION
In order to protect the unit from lightning surges entering
through signal and power supply cables, use of appropriate
lightning surge protectors are recommended. Please con-
tact M-System.