| Sensor Type | Terminal A (IN+) | Terminal B (IN-) | | --- | --- | --- | | 0-10 V voltage | Signal + | Common / GND | | 4-20 mA current | Signal + (via 250Ω internal shunt) | Common | | Thermocouple Type K | TC+ (positive lead) | TC- (negative lead) | | Pt100 (3-wire) | White (sense+) | Red (excitation) and White (return) |
A: The current version (VTM 10 Rev. 4) has SIL 2 capable hardware (certifiable) but is not shipped with a SIL certificate. For SIL 3, see the Altoc VTM 10S model. altoc vtm 10
: "Altoc VTM 10 mounted on DIN rail with labeled terminals for power, input, and output." | Sensor Type | Terminal A (IN+) |
A: The device will restart. Outputs go to the pre-set failsafe state for 10 seconds. Never update firmware in a live process without bypassing the safety logic. : "Altoc VTM 10 mounted on DIN rail
| Symptom | Likely Cause | Solution | | --- | --- | --- | | Green LED off | No power / reversed polarity | Check 24 VDC supply; swap terminals 1 and 2. | | Red LED flashing at 1 Hz | Sensor break or short | Check continuity of thermocouple/RTD. Is cable cut? | | Output stuck at 3.8 mA | Under-range condition | Input signal is below 0% of span. Check sensor zero. | | Output stuck at 20.5 mA | Over-range or burnout set | Input exceeds 105% of span, or sensor is broken with "high" burnout selected. | | Fluctuating output (noise) | VFD interference or filter off | Increase digital filter value; check shielding on input wires. Use twisted pair. | | No Modbus communication | Wrong baud rate / address | Verify settings match master. Ensure termination resistor (120Ω) is present on long runs (>100 m). |