MTT MS3121 Terminal Block Type PT Transmitter

The MTT MS3121 is a terminal block type PT transmitter with two independent, isolated outputs. It reads an AC voltage input from a potential transformer and converts it into two separate standard DC signals. It accepts 0~110V AC, 0~150V AC, or 0~300V AC at 50/60Hz, with input resistance of 1MΩ minimum, tolerating 120% of rated input continuously and 150% of rated input for up to 5 seconds, with a maximum crest factor of 3.

Output 1 and output 2 are independently isolated and configurable to 0~20mA DC, 4~20mA DC, or 0~10mV to ±10V DC (multiple voltage ranges) – useful when one signal needs to feed a PLC and a second, separate signal needs to feed a recorder or indicator at the same time. Output load is up to 750Ω for a single 4~20mA output, or 550Ω (output 1) and 350Ω (output 2) when both are used; voltage output load is 2mA max for 1V+ spans, 10kΩ min for a 10mV span, and 100kΩ min for a 100mV span. Zero and span are each adjustable by ±5% of span.

Accuracy is better than ±0.25% of span (at least 10% input, 25°C±5°C), with temperature effect better than ±0.2% of span per 10°C and response time of 400ms max (0-90%). CMRR is 100dB minimum, with 4-way isolation between input, output 1, output 2, and power.

Power supply is flexible: 100-240V AC (85-264V AC, 47-63Hz) at approximately 6.5VA, 24V DC ±10% at approximately 1.6W, or 110V DC (90-121V DC) at approximately 2.5W. The unit mounts on DIN rail, in an ABS resin (UL 94V-0) housing measuring 49.8mm × 102.0mm × 40.0mm and weighing under 140g.