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$995.00 (USA and Canada only)

Availability: In stock
Analog input, temperature (RTD) or resistor, 8 channels

Production Specification

The GRV-IRTD-8 analog input module is part of the groov EPIC® system. This module provides 8 input channels, each individually software configurable.

This module is commonly used for 3-wire RTD temperature inputs but is also suited to high-resolution resistance measurements. You can individually configure each of the module's 8 channels for a
fixed range in ohms or choose from two methods of auto-ranging:
  • Full Auto-range—The module scrolls up and down the entire set of ranges and dynamically chooses the appropriate range for best resolution. Note that this channel type can result in higher latency when ranging up; the data returned is resistance in ohms.
  • Auto-range Down—The module scrolls down and up within the specified range limit. If the value goes above the specified range, the module issues an out-of-range value (16-bit). These channel types allow auto-ranging within the selected range but limit the data latency when ranging up. The data returned is resistance in ohms.
The GRV-IRTD-8 module does not offer channel-to-channel isolation, so make sure you use isolated RTD probes.

The GRV-IRTD-8 module mounts on a groov EPIC® chassis with a GRV-EPIC-PR1  processor and assorted discrete, analog, and serial groov I/O modules.







Offset and Gain



Minimum/Maximum Values



Average Filter Weight



Simple Moving Average (SMA)



Analog Totalizing



Problem indication






Input Ranges (Ohms)

8.0 K, 4.0 K, 2.0 K, 1.0 K,
800, 400, 200, 100,
80, 40, 20, 10, and Autoranges

Accuracy (Ohms @ Range)

4.2@8 K, 2.6@4 K, 1.8@2 K, 1.4@1 K,
0.47@800, 0.31@400, 0.23@200, 0.19@100,
0.082@80, 0.066@40, 0.058@20, 0.058@10 Ohms

Excitation RMS Current
(Range & Load Watts Dissipated)

>301 µA (8 K & 363 µW), (4 K & 182 µW), (2 K & 91 µW), (1 K & 46 µW),
>1.84 mA (800 Ohms & 1.355 mW), (400 Ohms & 677 µW), (200 Ohms & 339 µW), (100 Ohms & 169 µW),
>3.96 mA (80 Ohms & 627 µW), (40 Ohms & 313 µW), (20 Ohms & 156 µW), (10 Ohms & 78 µW)

Data Refresh Time

600 ms

Analog Data Filtering

-3 dB @ 23.5 Hz / -18 dB @ 60 Hz

Software Filtering: Simple Moving Average (SMA)

1 to 32 readings

Software Filtering: Weighted Average

1 to 4096

Step Input Response Time

600 ms x SMA value (19.2 s @ 32 SMA, Default SMA = 4)

Total Lead Resistance1

200 Ohms Max

Problem Indication

out of range

Isolation (field-to-logic)

300 V working, 1500 V transient (1 minute)

Isolation (channel-to-channel)

300 V between channel group 0-3 & group 4-7. None within a group.

Number of Channels


Chassis Power Consumption

1.3 W

Minimum GRV-EPIC-PR1 Firmware Version


Minimum PAC Project Version


Minimum Library Package for CODESYS Version

Wire Size

28-14 AWG

Torque, connector screw

2.5 in-lb (0.28 N-m)

Torque, hold-down screw

3.5 in-lb (0.4 N-m)

Temperature (operating)

-20 °C to +70 °C

Temperature (storage)

-40 °C to +85 °C

Humidity (non-condensing)

5-95% RH

Agency Approvals

UL/cUL (Class 1 Div. 2)a, CE, ATEX (Category 3, Zone 2), RoHS, DFARS; UKCA



a For use in hazardous locations, equipment must be mounted in an enclosure that meets the requirements of the National Electrical Code, ANSI/NFPA 70, and ANSI/ISA-61010-1 (82.02.01).

1. The sum of the resistance in both lead wires cannot exceed this value. For example: a 24 AWG wire would need to be longer than 4,000 feet (or 1.2 kilometers), in each lead, to exceed 200 Ohms.

groov Thermistor Resistor Input Modules Data Sheet

groov analog input modules are part of Opto 22's groov EPIC® System. This document includes descriptions, specifications, and wiring and dimensional diagrams for groov thermistor/resistor analog input modules, part numbers GRV-IRTD-8 and GRV-ITR-12.

groov I/O Modules Firmware Release Notes

This document lists the latest updates to the firmware for groov I/O modules. It includes information on new features, enhancements, and bug fixes.

List of groov I/O module firmware download pages

Note: This document was formerly called a readme. The name was changed to more accurately describe its content.

UKCA Declaration of Conformity (groov EPIC and groov RIO)

This document is the Manufacturer's Declaration of Conformity for the products listed herein, in accordance with the rules, regulations and standards of the United Kingdom. The models cited have been tested to the essential requirements listed in the Standards section, and fully comply with the legislation as listed in UK Legislation section.

ATEX Letter of Conformity for groov EPIC

This ATEX Letter of Conformity is provided to support CE Declaration of Conformity (groov EPIC and groov RIO), form 2261.

Declaration of Conformity (groov EPIC and groov RIO)

This document is the Manufacturer's Declaration of Conformity for the products listed herein, in accordance with European, international, and/or national standards and regulations.

GRV-IRTD-8 Module Firmware

This download contains current firmware for the GRV-IRTD-8 module. For a list of bug fixes and enhancements included in this firmware, see the groov I/O Modules Firmware readme document.

You can obtain previous versions of the firmware by clicking on the corresponding link: 1.3c1.3b

CAD Drawing: groov I/O Module

This ZIP file includes drawings in a variety of file formats (pdf, dwg, stp) that apply to all groov I/O modules.

Note: These drawings do not apply to groov RIO modules.

CAD Drawings: groov EPIC and groov RIO I/O wiring

This ZIP file contains I/O wiring diagrams for groov EPIC I/O modules and groov RIO models, in DWG format.

No videos or demos are available for this product.