1734-IR2 — POINT I/O 2-Channel RTD/Resistance Input Module

The 1734-IR2 is a 2-channel RTD input module for the POINT I/O system, reading resistance signals directly from temperature sensors without requiring an external transmitter to convert resistance to a standard current or voltage signal first. Each of the two single-ended, non-isolated channels accepts a range of common RTD types, or can be wired directly to a 0–600 Ω resistance signal from another resistive sensor or transducer.

Specifications

Parameter	Value
Part Number	1734-IR2
Platform	POINT I/O (1734)
Input Channels	2 (single-ended, non-isolated)
Resistance Range	0–600 Ω
Compatible RTD Types	100/200 Pt (α=0.00385 or 0.003916), 10 Cu, 100/120 Ni
Resolution	16-bit (9.5 mΩ/count; ~0.03°C/count for Pt385)
Absolute Accuracy	0.1% full scale @ 25°C
Conversion Type	Delta-sigma
Common/Normal Mode Rejection	120 dB
POINTBus Current	220 mA @ 5V DC
Power Dissipation	1.0 W max
Operating Temperature	0°C to 55°C

RTD Input Without a Separate Transmitter

RTDs change resistance with temperature, and the 1734-IR2 reads that resistance change directly — no separate signal conditioner or transmitter between the sensor and this module's input. This simplifies the field wiring path and removes an extra device that could otherwise drift, fail, or require its own calibration. For applications already wired with a standard RTD sensor on a process vessel, motor winding, or ambient measurement point, this module connects directly without modification to the existing sensor.

Because the channels are non-isolated, both inputs share a backplane reference, so cabling routing matters more here than on an isolated alternative — keeping the RTD signal wiring separated from power and high-frequency switching cables reduces the noise pickup that a 16-bit resolution input is otherwise sensitive to over longer cable runs.

FAQ

Q: Does this module require an external power supply for the RTD sensors?

No. RTDs are passive resistive elements — the module supplies the small excitation current needed to measure resistance internally, with no external 24V DC supply required for sensor operation.

Q: Can the 1734-IR2 be wired to a non-RTD resistive sensor instead?

Yes. Any sensor or transducer producing a 0–600 Ω resistance output can be wired to this module's input, even if it isn't a standard RTD type — the module reads resistance directly regardless of the source.

Q: Is this module protected against an input overload condition?

No. The 1734-IR2 does not include input overload protection — care should be taken during wiring and commissioning to avoid applying signals outside the module's rated input range.

Q: What terminal base is required for this module?

Standard 1734-TB, 1734-TBS, 1734-TOP, or 1734-TOPS terminal base assemblies are compatible — select based on the panel's preferred terminal style and any need for the quick-disconnect TOP/TOPS variants.

1734-IR2 New Sealed 1734IR2 Ser C POINT I/O 2 RTD Input Module