I. Positioning (to distinguish from the previous cables / base plate)

4000094/098/103: AI/AO/DI/DO cables

4000163: Expansion base plate / chassis

4000164-520: DI input module (inserted on the base plate)

II. Core parameters (reduced version)

Module type: High-density digital input DI module

Channel count: 16 channels (120VAC nominal)

Architecture: TMR triple redundancy (3 independent acquisitions per channel + hardware voting)

Safety level: SIL2 (IEC 61508/61511)

Isolation: Channel-to-channel, channel - system complete isolation

Diagnosis: Online diagnosis, open circuit detection, internal circuit health monitoring

Backplane communication: Tricon dedicated high-speed redundant bus

Operating voltage: 10–30VDC

Temperature: -20℃ ~ +70℃

Certification: CE, UL, CSA, SIL2

Weight: Approximately 0.85 kg

III. Naming rules (abbreviated)

4000164: High-density DI module series

520: Specification code → 16ch / 120VAC / TMR

IV. Common items in the same series (for comparison)

4000164-510: 16ch / 24VDC DI

4000164-520: 16ch / 120VAC DI (your model)

4000164-530: 32ch / 24VDC DI

V. One-sentence distinction (very important)

4000163-510: Base plate (the frame for installing modules)

4000164-520: DI module (inserted on the frame to collect switch quantities)