Myron L 767 - Manual (Page 9)

Installation
2.4.2 220 VAC CONVERSION
STEP 1 Verify that the facility’s main AC power source is turned
“OFF” or disconnected.
STEP 2 Locate and remove the Control board jumpers E1 and
E3. (See Fig. 2-6.)
STEP 3 Using one of the removed jumpers, insert it into jumper
E2’s connection holes as shown in Fig. 2-6.
2.5 0-10 VDC RECORDER OUTPUT
STEP 1 Place the user supplied interface cable and watertight
cable restraint into the enclosure’s appropriate access
hole.
STEP 2 Connect the Recorder’s plus (+) and minus (-) terminal
wires to the Recorder output’s TB connectors. (See Fig.
2-4 or 2-5)
STEP 3 Refer to Section 4.3.2 for the procedures to calibrate
the 0-10 VDC voltage output
2.6 CONNECTING THE MODEL 758 4-20mA AND 420D
OPTIONS
STEP 1 Place the user supplied cable and watertight cable
restraint into the enclosure’s appropriate access hole.
STEP 2 Neatly insert cable wires into the 758 Panel board’s
plus (+) and minus (-) TB1 terminal block connectors as
shown in Fig. 2-7.
STEP 3 See Section 4.3.3 to calibrate the 4-20mA minimum
and maximum current outputs.
2.7 INSTALLATION OF THE MODEL 767 OPTIONS
The Model 767 Conductivity Monitor/Controller can be
configured with a combination of options. Based upon user
requirements, the electrical installation of one or more of the
following options may be required.
2.7.1 CONNECTING THE 767-420D OPTIONS
STEP 1 Place the user supplied cable and watertight cable
restraint into the enclosure’s appropriate access hole.
STEP 2 Neatly connect the cable wires to the Monitor’s plus (+)
and minus (-) terminals TB1-4 & 5. (See Fig. 2-5.)
STEP 3 Refer to Section 4.3.5 for the procedures to calibrate
the Model 767’s 4-20mA minimum and maximum
current outputs.
NOTE:
The maximum impedance of the user’s current sensor should
not exceed 400 ohms.
2.7.2 CONNECTING THE REMOTE METER OPTION
STEP 1 Connect the Remote Meter cable and user supplied
restraint into the enclosure’s appropriate access hole.
STEP 2 Neatly connect the Remote Meter’s positive (+) and
minus (-) wires to terminals TB1-13 &14. (See Fig. 2-5.)
STEP 3 Refer to Section 4.3 for the procedures to calibrate the
Model 767’s Remote Meter output.
2.4.3 CONNECTING THE CELL CABLE
STEP 1 Place the Cell’s interface cable and user supplied
watertight cable restraint into the enclosure’s
appropriate access hole.
STEP 2 Neatly connect the Cell’s cable wires to the Monitor’s
appropriate TB connectors. (See Fig. 2-4 or 2-5.)
2.4.4 ALARM RELAY INSTALLATION
STEP 1 Place the user supplied Alarm relay interface cable and
watertight cable restraint into the enclosure’s
appropriate access hole.
STEP 2 Neatly connect the Relay cable wires to the Monitor’s
TB connectors (See Fig 2-4-1 or 2-5-1) as explained
below. All Myron L Company Conductivity Monitor/
Controllers (except Model 756) are equipped with a
relay which is designed to energize/de-energize when
the set point is crossed. (See P.10, sec 3.3.2 for set
point adjustment procedure) The relay energizes on
increasing readings. The easiest method of connecting
the relay is shown below in FlGs 2-4-1 and 2-5-1.
These show how the dry contact relay can use
incoming power to activate a controlled device (alarm,
solenoid valve, etc.) of 10 amps or less. A user-
supplied transformer is necessary if the controlled
device operates on a voltage different from the voltage
which powers your Myron L monitor/controller. An
alternative (necessary if the device is DC powered) is
to connect a separate, second power source to the
relay.
When energized (above set point), the Common (COM) will
disconnect from the Normally Closed NC contact and connect to
the Normally Open (NO) contact. Devices may be operated
using either the Normally Open contact or Normally Closed
contact; or both relay contacts may be used to activate two
devices of the same voltage.
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