MTL4546S ISOLATING DRIVER

for 4–20mA HART® valve positioners with line fault detection and long field lines

The MTL4546S accepts a 4/20mA floating signal from a safe-area

controller to drive a current/pressure converter (or any other load up to

710Ω) in a hazardous area. For HART valve positioners, the module also

permits bi-directional transmission of digital communication signals.

Process controllers with a readback facility can detect open circuits in

the field wiring: if these occur, the current taken into the terminals drops

to a preset level. The reduced maximum open-circuit voltage permits

the use of longer field lines compared to MTL4546

SPECIFICATION

See also common specification

Number of channels

One

Location of I/P converter

Zone 0. IIC, T4–6 hazardous area if suitably certified

Div. 1. Group A, hazardous location

Working range

4 to 20mA

Digital signal bandwidth

500Hz to 10kHz

Maximum load resistance

710Ω (14.2V at 20mA)

Minimum load resistance

90Ω

Output resistance

> 1MΩ

Under/over range capability

Under range = 1mA

Over range = 24mA (load ≤ 520Ω)

Input and output circuit ripple

< 40µA peak-to-peak