The MTL646 and MTL647 indicators are intrinsically safe instruments that can display text and simple graphics in a hazardous area. With
two solid-state switched outputs, MTL646 and MTL6547 indicators provide a low cost operator interface ideal for simple machine and process
control applications.
Data and power for the MTL646 and MTL647 are normally supplied by a 2-wire serial data link from an MTL5051 isolator in the safe area. This
isolator, which can power and communicate with up to two MTL646/647 serial text displays, has a bi-directional RS232 or RS422 safe area port.
Bi-directional communication permits operators to acknowledge messages and to request process action when necessary. If required, an audible
or visual alarm can be connected to attract the operator's attention.
Six push-buttons on the front panel of the MTL646 (four on the MTL647) may be used for operator acknowledgments or controls.The high contrast
LCD incorporates a green backlight that is powered by the serial data link. Brightness and contrast are adjustable enabling the display to be
read in all lighting conditions from full sunlight to total darkness. Two isolated switch outputs, which can control certified hazardous area
loads such as sounders, lamps and valves, are included.
Five different operational modes are selectable, allowing the user to choose the appropriate level of communications security for each application.
These range from immediate execution of a command with no message acknowledgement, to a 16 bit CRC. The communications speed, number of stop bits
and polarity of the parity bit can also be defined.
The MTL647 is a field mount unit housed in a tough impact-resistant case designed to withstand the rigors of hostile weather conditions and harsh
industrial environments. Ingress protection rating is IP66. It can be mounted directly onto a flat surface or, with an optional kit, onto vertical
or horizontal pipes or posts.
The MTL646 is a panel mounted unit designed for DIN standard 72 x 144mm cut-out. The panel/unit seal is rated at IP40 while, with standard ‘snap-on'
mounting clips, the panel/unit seal is rated IP40. This can be uprated to IP65 using four mounting clips.
