MTL’s multiplexing system reduces the cost of laying hazard zone cables by sending and receiving input and output signals from single or double redundant pairs of lines.
MTL multiplexer selection
MTL800 series ampere multiplex converter system, only through 2 wires, the danger zone multiplex signal transmission to the safe zone. MTL831B multiway transmitter is usually installed in dangerous situations, it is connected with the field sensor or switch, through a single pair of data link to transmit these input signal status to the safe area, the data link supports the communication between the danger zone and the safe zone, using MTL’s own communication protocol, of course, also provides power to the transmitter, no need for field power supply.
Typical use of the MTL831B is in an ENC83 case close to the field instrumentation.
MTL831B analog input transmitter
Monitor up to 16 thermocouples or millivolt sources (Max + / – 60mV) or 15 2,3,4 wire heating resistors in hazardous situations.
1. Intrinsically safe, applicable to zone 0
2. The communication and power supply pass through a pair of data links
3. Supply power to the data link
4. Thermocouple and thermal resistance can be used in the same transmitter
Two MTL831B multiplexers can share an isolator or receiver or a combination of the same single pair data link to the security zone, providing up to 32 multiplexed inputs.
Data link cable
There is no special requirement for data link cable, simple twisted pair or multi-core cable will do. In some cases, only one data wire is required, but in critical systems, a second data wire is configured for redundancy. The longest data link in the danger zone should not exceed 2KM, and the longest data link in the security zone should not exceed 3KM.
case
In the field, MTL831B components can be mounted in steel or stainless steel cases. ENC8SS(stainless steel) provides protection for a single MTL831B with IP67 dust and water resistance rating. When 4-wire heating resistors are used, the ENC83SS (stainless steel) case provides additional terminals for connecting the third and fourth wires of the thermal resistors instead of to the MTL831B assembly.