Yokogawa MLD - Manual (Page 5)

IM 61A01A01-01E-A
4. WIRING
The loop powered indicator series is powered by the current output loop and does not require external
power. All devices must be wired in series with the current loop. Twisted pair shielded cable is
recommended.
The following is a typical wiring example of the MLA (Analog type) Loop Indicator connected to an
EJA Pressure Transmitter. The impedance of the MLA is low enough that you can connect it
across the Check Terminals
The following is another wiring example of the MLA (Analog type) or MLD (Digital type) Loop Indicator connected to an EJA
Pressure Transmitter (Note: The EJA Transmitter below can be replaced with any 4-20mA 2 wire device.
The Loop Indicator is available in FM Explosion Proof and CSA Explosion Proof types for hazardous
locations. Wire sealing is required for these approvals. The following diagrams show some wire sealing