CHECKING
1) Terminal wiring: Check that all cables are correctly con-
nected according to the connection diagram.
2) Power input voltage: Check voltage across the terminal
7 – 8 with a multimeter.
3) Input: Check that the input signal is within 0 – 100% of
the full-scale.
Be sure to short the secondary side of CT or turn off the
current at its primary side for preventing the CT from
burning when the cables are to be disconnected from in-
put terminals.
4) Output: Check that the load resistance meets the de-
scribed specifications.
5) With 100% input, check that the voltage across the ter-
minal 3 – 4 shows 0.18 V AC or less. If it exceeds 0.18V
AC, polish the transmitter’s base plug with a clean cloth.
ADJUSTMENT PROCEDURE
This unit is calibrated at the factory to meet the ordered
specifications, therefore you usually do not need any cali-
bration.
For matching the signal to a receiving instrument or in case
of regular calibration, adjust the output as explained in the
following.
■
HOW TO CALIBRATE THE OUTPUT SIGNAL
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).
MAINTENANCE
Regular calibration procedure is explained below:
■
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.
CTH
5-2-55, Minamitsumori, Nishinari-ku, Osaka 557-0063 JAPAN
Phone: +81(6)6659-8201 Fax: +81(6)6659-8510 E-mail: [email protected]
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