Eaton MTL4546/C/Y – MTL5546/Y ISOLATING DRIVER

MTL4546/C/Y – MTL5546/Y ISOLATING DRIVER

for 4–20mA HART® valve positioners with line fault detection

The MTLx546 accepts a 4/20mA floating signal from a safe-area controller

to drive a current/pressure converter (or any other load up to 800Ω) 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 or short circuits in

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

to a preset level. The MTL4546C and the MTLx546Y are very similar

to the MTLx546 except that they provide open circuit detection only

(i.e. no short-circuit detection).

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

800Ω (16V at 20mA)

Minimum load resistance

90Ω (short-circuit detection at < 50Ω)

Output resistance

> 1MΩ

Under/over range capability

Under range = 1mA

Over range = 24mA (load ≤ 520Ω)

Input and output circuit ripple

< 40μA peak-to-peak

Transfer accuracy at 20°C

Better than 20μA

Temperature drift

< 1.0μA/°C

Response time

Settles within 200μA of final value within 100ms

Communications supported

HART

LED indicator

Green: power indication

Maximum current consumption (with 20mA signals into 250Ω load)

35mA at 24V dc

Power dissipation within unit (with 20mA signals into 250Ω load)

0.8W at 24V

Safety description

Vo

=28V   Io

=93mA  Po

=651mW  Um = 253V rms or dc

SIL capable

These models have been assessed for use in IEC 61508 functional

safety applications. See data on MTL web site.