MEX-D VALVE POSITIONER
MEX-D
Final Control Elements
VALVE POSITIONER
(current feedback; built-in SSR)
Functions & Features
• Controlling an electric actuator powered with 100 V AC
• Feedback current 4 – 20 mA DC
• Builtin SSR directly drives an AC motor
• Timer for motor's overheat protection
• Re-transmitted output
Typical Applications
• Single phase AC motor
• Loop powered isolator can be used for isolating between setpoint input signal and transmitter output signal
MODEL: MEX–D–[1][2]
ORDERING INFORMATION
• Code number: MEX-D-[1][2]
Specify a code from below for each of [1] and [2].
(e.g. MEX-D-B/Q)
• Specify the specification for option code /Q
(e.g. /C01/S01)
[1] POWER INPUT
AC Power
B: 100 V AC
C: 110 V AC
D: 115 V AC
F: 120 V AC
G: 200 V AC
H: 220 V AC
J: 240 V AC
[2] OPTIONS
blank: none
/Q: With options (specify the specification)
SPECIFICATIONS OF OPTION: Q (multiple selections)
COATING (For the detail, refer to our web site.)
/C01: Silicone coating
/C02: Polyurethane coating
/C03: Rubber coating
TERMINAL SCREW MATERIAL
/S01: Stainless steel
GENERAL SPECIFICATIONS
Construction: Plug-in
Connection: M3.5 screw terminals
Screw terminal: Chromated steel (standard) or stainless steel
Housing material: Flame-resistant resin (black)
Deadband adjustment: 2 – 20 % (front)
Timer adjustment: 1 – 30 sec. (front)
Isolation: Input or xmtr output to output to power
Zero adjustment: -10 to +10 % (front)
Span adjustment: 90 to 110 % (front)
INPUT SPECIFICATIONS
■ Setpoint Signal: 4 – 20 mA DC; input resistor incorporated
Input resistance: 100 Ω
■ Feedback Current: 4 – 20 mA DC; input resistor incorporated
Input resistance: 20 Ω
OUTPUT SPECIFICATIONS
■ Re-Transmitted Output: 4 – 20 mA DC
Load resistance: 750 Ω max.
■ Control Output: SSR (zero-crossing);
60 – 280 V AC @ 0.1 – 1 A
Note 1: The incorporated SSR is not capable for driving 200 V AC motor.
Note 2: When driving relays with this control output, relays may operate erratically due to the leakage current at OFF of SSR. To avoid the problem, install a resistor (R) in parallel with the relay coil.
R < [Release Voltage] ÷ [[Leakage Current at OFF] – [Release Current]]
Leakage current at OFF: Approx. 10 mA @ 240 V
INSTALLATION
Power input
•AC: Operational voltage range: rating ±10 %,
50/60 ±2 Hz, approx. 3 VA
Operating temperature: -5 to +60°C (23 to 140°F)
Operating humidity: 30 to 90 %RH (non-condensing)
Mounting: Surface or DIN rail
Weight: 300 g (0.66 lb)
PERFORMANCE in percentage of span
Position conversion accuracy: ±0.5 %
Insulation resistance: ≥ 100 MΩ with 500 V DC
Dielectric strength: 1000 V AC @ 1 minute
(input or xmtr output to output to power)
2000 V AC @ 1 minute (input or xmtr output or output or power to ground)
EXTERNAL VIEW
EXTERNAL DIMENSIONS & TERMINAL ASSIGNMENTS unit: mm [inch]
SCHEMATIC CIRCUITRY & CONNECTION DIAGRAM
EXPLANATIONS OF TERMS
• SSR (Solid State Relay)
Composed only of semiconductor parts, SSR is free from arc discharge or chattering which is typical with electromagnetic relays. It features excellent characteristics against vibration, physical impact or other environmental conditions.
• Zero-Cross Function
SSR with zero-cross function turns on when AC power voltage is near zero, creating delay of switching when input is provided in the middle of an wave cycle, thus limiting transient switching noise voltage and rush current.
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CÔNG TY CỔ PHẦN KỸ THUẬT VÀ THƯƠNG MẠI THIẾT BỊ CÔNG NGHIỆP NTD
Adress: No. 28, Alley 36 Co Linh Street, Group 7, Long Bien Ward, Long Bien District, Hanoi City, Vietnam.
Hotline: 0971961212
Mail: sales@ntd-automation.com