2.4 Selecting Installation Locations
The transmitter is designed to withstand severe environmental conditions. However,
to ensure stable and accurate operation, the following precautions must be observed
when selecting an installation location.
1. Ambient Temperature
Avoidlocationssubjecttowidetemperaturevariationsorasignicanttemperature
gradient. If the location is exposed to radiant heat from plant equipment, provide
adequate insulation or ventilation.
2. Ambient Atmosphere
Avoid installing the transmitter in a corrosive atmosphere. If the transmitter must
be installed in a corrosive atmosphere, there must be adequate ventilation.
Precautions must be put into place to prevent intrusion or stagnation of rainwater
in conduits.
3. ShockandVibration
Select an installation site with minimum shock and vibration (although the
transmitter is designed to be relatively resistant to shock and vibration).
4. Installation of Explosion-Proof Transmitters
Explosion-Proof transmitters can be installed in hazardous areas according to the
gastypesforwhichtheyarecertied.
5. Select a place where the transmitter can be maintenanced easily.
2.5 Calibration after Installation
1. SensorZeroTrimshouldbedoneaftertransmitterisinstalled,becausethezero
pointisnotconguredformountingstatus.
2. When calibrating the Sensor Zero Trim apply a pressure for zero in advance,
Sensor Zero Trim the sensor when the pressure is sufciently stabilized (after
approximately 10 seconds).
3. There are two ways to pressure zero. One way is to apply zero differential pressure
(making pressure the same on both the high and low side). The other is to close
High and Low side of a 3 valve manifold and open the equalizing valve.
4. Sensor Zero Trimming can also be done with the Zero/Span button or a HHT
(HART®Communicator),PCorPDAcongurator.
5. RefertoOn-lineOperationforconguringotherparameters.
2.6 Pressure Connections
The following precautions must be observed in order to safely operate the transmitter
under pressure.
1. Neverapplyapressurehigherthanthespeciedmaximumworkingpressure.
2. Conrmtheoptionpressureoftransmitter.Itisnecessarytousestandardizedand
quality-approved parts.
3. There should be isolation valves in case of leakage.
2.7 Waterproong Cable Conduit Connections
Apply a non-hardening sealant (silicone or tape, etc.) to the threads to waterproof the
transmitter cable conduit connections.
2.8 Restrictions on Use of Radio Transceivers
2.9 Installation Resistance Test and Dielectric Strength Test
Since the transmitter has undergone insulation resistance and dielectric strength tests
at the factory, normally these tests are not required. However, if required, observe the
following precautions in the test procedures.
1. Do not perform such tests more frequently than necessary. Even test voltages,
that do not cause visible damage to the insulation, may degrade the insulation and
reduce safety margins.
2. Neverapplyavoltageexceeding500VDCfortheinsulationresistancetest,ora
voltageexceeding500VACforthedielectricstrengthtest.
3. Before conducting these tests, disconnect all signal lines from the transmitter
terminals. Perform the tests in the following procedures.
Insulation Resistance test
1. Short-circuit the + and - SUPPLY terminals in the terminal box.
2. Turn OFF the insulation tester. Then connect the insulation tester plus (+)
lead-wire to the shorted SUPPLY terminals and the minus (-) lead wire to the
grounding terminal.
3. Turn ON the insulation tester power and measure the insulation resistance. The
voltage should be applied briey to verify that insulation resistance is at least
20MΩ.
4. After completing the test and being very careful not to touch exposed conductors.
Disconnect the insulation tester and connect a 100kW resistor between the
grounding terminal and the shortcircuiting SUPPLY terminals. Leave this resistor
connected at least three seconds to discharge any static potential. Do not touch the
terminal while it is discharging.
Dielectric Strength Test
1. Short-circuit the + and - SUPPLY terminals in the terminal box.
2. Turn off the dielectric strength tester. Then connect the tester between the shorted
SUPPLY terminal and the grounding terminal. Be sure to connect the grounding
lead of the dielectric strength tester to the ground terminal.
3. Set the current limit on the dielectric strength tester to 10 mA, then turn on the
powerandgraduallyincreasethetestervoltagefrom‘0’tothespeciedvoltage.
4. Whenthespeciedvoltageisreached,holditforoneminute.
5. After completing this test, slowly decrease the voltage to avoid any voltage surges.
2.10 Explosion-Proof Rating
2-10-1. FM Certication
HAZARDOUSLOCATIONELECTRICALEQUIPMENT
Equipment Rating: Explosion-Proof for use in Class I, Division 1, Groups A, B, C
and D;
Dust- Ignition-Proof for Class II/III, Division 1, Groups E, F and G;
Nonincensive for use in Class I, Division 2, Groups A, B, C and D;
Suitable for use in Class II, Division 2, Groups E, F and G; and Suitable for Class
III, Division 1;
Hazardous(classied)location,indoorandoutdoor(NEMAType4X/IP67).
1. SupplyVoltage:42VDC max
2. Output Signal: 4-20 mA + HART
1. All wiring shall comply with local installation requirement.
2. The cableglands and blanking elements shallbe of a certied ameproof type,
suitable for the condition of use and correctly installed. Also those devices should
be endured at the 130°C.
3. Housing Ground must be followed to “local electrical codes”.The most efcient
ground procedure is to connect directly to the earth as least impedance.
1. How to Housing Ground:
A. Internal Ground Connection:
Internal ground connection screw is located in terminal in housing; the
screwcanbeidentiedasgroundsign.
B. External Ground Assembly:
Thisislocatedintherightsideofhousingandidentiedasgroundsign.
(Grounding with a cable lug)
2. When use tubing, stopping boxes must be connected with the wall of housing
directly.
3. Tubing is installed a minimum of 5 threads.
4. Sensor is to be threaded a minimum of 7 threads and prevented from turing by
tightening the housing rotation set screw.
5. Do not disassemble ameproof Joints but in an unavoidable case to
disassemble it or need the specication of ameproof Joints, contact the
manufacturer before doing.
1. Take care not to generate mechanical spark when access to the instrument and
peripheral devices in hazardous location.
The instrument modication or parts replacement by other than authorized
representative of Dwyer/Mercoid is prohobited and will void explosion-proof/
ameproof.
Instrument installed in the process under pressure. Never loosen
ortightenasitmaycausedangerousspoutingofprocessuid.If
theprocessuidistoxicorotherwiseharmful,takeappropriatecaretoavoidcontact
or inhalation of vapors even after disconnecting the instrument from process line for
maintenance.
CAUTION
Although the transmitter has been designed to resist high
frequency electrical noise, if a radio transceiver is used near the
transmitters external wiring, the transmitter may be affected by high frequency noise
pickup. To test for such effects, bring the transceiver in slowly from a distance of
several feet from the transmitter, and observe the measurement loop for noise affects.
Always use the transceiver outside the area affected by noise.
WARNING
Electrical Data
NOTICE
Electrical Connection : 2 x 1/2-14 NPT Female
NOTICE
Installation
NOTICE
Operation
NOTICE
DONOTOPENWHENANEXPLOSIVEATMOSPHEREMAYBE
PRESENT.
WARNING
Maintenance and Repair
NOTICE
