1769-IT6 CompactLogix 6 Pt Thermocouple PLC Module

Product Introduce

The 1769‑IT6 is a 6-channel thermocouple millivolt input module from the 1769 Compact I/O series with scan periods as fast as 1 ms/channel.

Products Specifications

Parameter	Value
Input Channels	6 channels (thermocouple/mV), channel‑to‑channel isolation
Supported Thermocouples	B, E, J, K, N, R, S, T, C types
Input Range	±75 mV (mV mode); TC ranges per type
Resolution	16‑bit
Update Rate	2.5 ms per channel
Cold Junction Compensation (CJC)	Built‑in dual sensors, auto‑compensation
Backplane Power	5V @ 100 mA, 24V @ 40 mA (no external power needed)
Isolation	Channel‑to‑channel, channel‑to‑backplane (30V AC/DC working, 720V DC surge)
Dimensions	118 mm (H) × 32 mm (W) × 87 mm (D)
Lifecycle	Active Mature (as of Dec 2025)
Key Docs	1769‑TD006 (tech data), 1769‑UM021 (user manual)

FAQ

1.The channel-to-channel isolation voltage of 1769-IT6 is 30V AC/DC. In a high-interference industrial environment, how to further optimize anti-interference measures?

Hardware hardening:

1. Each channel is connected in series with a dedicated thermocouple isolator (isolation voltage ≥1500V AC) to block ground loops and common mode interference.
2. Connect a 100Ω+100nF RC filter in parallel to the terminals, or use a magnetic ring to suppress high-frequency spikes.
3. The controller is equipped with an isolation transformer + surge suppressor to purify the power supply.

Wiring specifications:

1. Use twisted-pair shielded wires, and the PLC side of the shielding layer should be grounded at one end.
2. The distance between signal cables and power cables should be ≥30cm. When crossing, they should be 90° vertical and away from interference sources such as frequency converters.

Software optimization:

1. In Studio 5000, set the filter frequency to 50/60Hz and enable 10–20ms digital filtering.
2. Add “two out of three” or sliding average algorithm to the program to filter instantaneous jump data

Grounding and installation:

1. Analog ground and digital ground are grounded at a single point (ground resistance <1Ω).
2. 1769 The backplane and the cabinet are installed insulated, and the cabinets are equipped with equipotential connections.

Verification method: short-circuit the channel thermocouple, and the reading is stable at the module terminal temperature ±1°C, which means the standard is met.

2.1769-IT6 does not require an external power supply. Can the backplane power supply meet the needs of 6-channel simultaneous acquisition?

The 1769-IT6 backplane power supply fully meets 6-channel simultaneous acquisition:

1. Power consumption parameters: 5V DC maximum 100mA, 24V DC maximum 40mA, which is far lower than the upper limit of single slot power supply of 1769 backplane (5V≥500mA, 24V≥200mA).
2. Design features: multi-channel shared conversion circuit, 6-channel simultaneous acquisition of power consumption without superposition, heat consumption of only 1.5W, and no risk of overheating.
3. Boundary Note: There should be no more than 4 high-power consumption modules on the same backplane. Ensure that the power terminals are firmly crimped and the grounding resistance is <1Ω.