18KRS
5-2-55, Minamitsumori, Nishinari-ku, Osaka 557-0063 JAPAN
Phone: +81(6)6659-8201 Fax: +81(6)6659-8510 E-mail: [email protected]
EM-0414 Rev.1 P. 3 / 3
WIRING INSTRUCTIONS
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SCREW TERMINAL
Torque: 0.8 N·m
CHECKING
1) Terminal wiring: Check that all cables are correctly con-
nected according to the connection diagram.
2) Power input voltage: Check voltage supplied to the rack
(model: 18KBXx). For the DC power source, be sure that
the ripple level is within 10% p-p.
3) Input: Check voltage across the terminal 1 – 2 with a
sensitive voltmeter (With 20°C or 68°F, approx. 220mV
with Pt 100, approx. 110mV with Pt 50 Ω).
If RTD wires are broken, the output goes over 100% (be-
low 0% with downscale) due to burnout 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.
The output signal can be finely adjusted to match it to a re-
ceiving instrument, or to compensate input wire resistance
when the unit is combined with a zenor barrier. Follow the
regular calibration procedure explained below:
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HOW TO CALIBRATE THE OUTPUT 1
Use a signal source and measuring instruments of sufficient
accuracy level. Turn the power supply on and warm up for
more than 10 minutes.
1) ZERO: Apply 0% input and adjust output to 0%.
2) SPAN: Apply 100% input and adjust output to 100%.
3) Check ZERO adjustment again with 0% input.
4) When ZERO value is changed, repeat the above proce-
dure 1) – 3).
5) No need of adjustments for the Output 2.
MAINTENANCE
Regular calibration procedure is explained below:
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CALIBRATION
Warm up the unit for at least 10 minutes. Apply 0%, 25%,
50%, 75% and 100% input signal. Check that the output
signal for the respective input signal remains within accu-
racy described in the data sheet. When the output is out of
tolerance, recalibrate the unit according to the “ADJUST-
MENT PROCEDURE” explained earlier.
LIGHTNING SURGE PROTECTION
M-System offers a series of lightning surge protector for
protection against induced lightning surges. Please contact
M-System to choose appropriate models.
