The Clark Reliance Corporation
16633 Foltz Industrial Parkway | Strongsville, OH 44149 | Tel1 (440) 572-1500 Facsimile: +1 (440)-238-8828
Email:
| Web Site:
www.clark-reliance.com
ENVIRONMENTAL
Humidity:
0 to 100% R.H., non-condensing
Electronics Operating Temperature:
-30 to 160°F (-34 to 71°C) ambient
Vessel Pressure:
Dependent on float pressure rating,
FIELD INSTALLATION
Mounting:
3/4 in. NPT fitting or flange mounting
Wiring:
2-wire connection, shielded cable or twisted pair to screw
terminals through a 3/4 in. NPT conduit opening
DISPLAY
Measured Variables:
Level
Update Rate:
3 seconds
HART COMMUNICATIONS
Method of Communication:
Frequency Shift Keying (FSK) conforms with Bell 202
Modem Standard with respect to baud rate and digital “1”
and “0” frequencies.
Baud Rate:
1200 BPS
Digital “0” Frequency:
2200 Hz
Digital “1” Frequency:
1200 Hz
Data Byte Structure:
1 Start Bit, 8 Data Bits, 1 Odd Parity Bit, 1 Stop Bit
Digital Process Variable Rate:
Poll/Response Model 2.0 per second
AGENCY APPROVALS
Factory Mutual (FM)
Explosion-proof:
Class I, Div 1, Groups B, C, D
Class II, Div 1, Groups E, F, G
Class III
2.2 Theory of Operation
The MTII4200 transmitters precisely sense the position of an external float by applying an interrogation pulse to a
waveguide medium. This current pulse causes a magnetic field to instantly surround the waveguide. The magnet installed
within the float also creates a magnetic field. Where the magnetic fields from the waveguide and float intersect, a
rotational force is created (waveguide twist). This, in turn, creates a torsional sonic pulse that travels along the waveguide.
The head of the transmitter houses the sensing circuit, which detects the torsional sonic pulse and converts it to an
electrical pulse. The distance from a reference point to the float is determined by measuring the time interval between the
initiating current pulse and the return pulse and knowing the precise speed of these pulses. The time interval is converted
into a 4 - 20 mA loop signal.
3. INSTALLATION/MOUNTING
Mounting
The MTII4200 is designed to mount directly to the outside of the Magnicator II chamber.
1. Secure the transmitter to the chamber using the supplied hose clamps.
2. Align the low and high level range markings on the sensor housing with the actual measurement range .
3. Ensure that the clamps are tight.
4. To test if the gauge is properly tightened, pull up on the electronics housing. The gauge should not move.
