Myron L 729II - Manual (Page 28)

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FATAL TO PERSONNEL. ONLY QUALIFIED PERSON-
NEL SHOULD INSTALL ELECTRICAL EQUIPMENT.
Physical
If the front panel has all ready been removed from the enclosure
skip to #3.
1. Using a standard slot screwdriver remove the four (4)
screws on the front panel.
2. Carefully wiggle the front panel to loosen and pull gently
toward you. Do not pull more than about 8 inches/
20CM or you could damage the wiring harness.
3. Turn the front panel around so that the back side is
facing you.
4. Using a standard slot screwdriver remove the four (4)
screws holding the plastic display retainer plate to the
front panel. When the screws have been removed, the
plastic display retainer plate and the display will be free
from the front panel.
5. Set front panel down or carefully allow to hang from the
harness. Do not drop as the harness connector will pull
out allowing the front panel to fall.
6. While holding the display and the plastic display retainer
plate, carefully remove the display harness connector.
Do not drop the display. Remove and discard the plastic
display retainer plate.
7. While still holding the display in the palm of your hand,
set the 4-20 Module over it with the display pins
protruding through the center opening as shown in
figure III.B.3.
8. Reconnect the harness to the display as shown in
figure III.B.3.
9. While holding the front panel, align the display to the
opening while at the same time align the 4-20 Module
mounting holes to the front panel.
10. Reinstall the four (4) screws and tighten.
Electrical
1. Connect the 4-20 Module (five) 5 wire harness to the
main circuit board at the location next to the display
harness marked “4-20” as shown in figure III.B.4.
2. Connect the signal and power wires as required, as
shown in figures III.B.1. & III.B.2. This assumes you
have already connected the other end of the wires as
required.
a. Place the remote interface cable and user supplied
watertight cable restraint into the enclosure’s
appropriate access hole.
b. Neatly connect the signal cable wires to the
Monitor’s appropriate connectors as shown in
figure III.B.3.
3. To test, turn power ON.
4. Press the Full Scale Test switch and monitor the output
at your remote site, or with a DVM set to DC milliamps.
Attach the DVM to the output connectors per your
requirements, i.e. self-powered or remote-powered, see
figures III.B.1. & III.B.2. If the 4A module is connected
properly it will indicate 20mA.
5. Turn power OFF.
6. Carefully reinstall the front panel, bottom first, ensure no
wires have been pinched between enclosure and front
panel.
7. Reinstall the four (4) screws and tighten.
8. To operate, turn power ON.
3. RECALIBRATION
The 4-20 Module was calibrated at the factory; however, if you
wish to check the calibration the following procedure will help
you to accomplish this task. Exercise caution while performing
this procedure.
Requirements ; a DVM set to DC milliamps, a tweaker or small
standard slot screwdriver.
This procedure assumes the front panel is removed.
For Resistivity models, please follow special notes (*)
1. If sensor is connected, disconnect sensor wires from
sensor terminal block. (* For Resistivity models,
connect the sensor wires (red, green, & neutral)
into the sensor terminal block. Use a jumper to
bridge the black and white terminals together.)
2. Attach the DVM to the output connectors per your
requirements, i.e. self-powered or remote-powered,
see figure III.B.5.
3. FOR RESISTIVITY ONLY: Add jumper between
Black(BK) and White(WT) connectors, see Figure III.B.4.
For Conductivity, go to step 4.
4. Turn power ON, with the front panel meter/display at
ZERO, the DVM should indicate 4 milliamps.
Figure III.B.3.
4 20
DISPLAY
4A/4AO - 4-20mA MODULE
4-20
(+)
(-)
+
-
(+) SIGNAL OUT
POWER OUT
POWER IN +
TO CIRCUIT BOARD
DISPLAY IS ON BACK SIDE OF 4-20 MODULE
RECONNECT
DISPLAY
CONNECTOR
HERE
SO PO PI