Description
The Emerson / GE Fanuc VersaMax IC200ALG620 is a 4-channel, 16-bit resolution analog input module designed for direct interface with Resistance Temperature Detectors (RTDs) and linear resistance sensors. Operating directly on the VersaMax I/O backplane, this module provides precision temperature conversion for up to four independent 3-wire or 4-wire RTD devices without requiring external loop power supplies or external excitation sources.
Technical Specifications
| Parameter | Specification / Value |
| Brand / Manufacturer | Emerson Automation Solutions (Formerly GE Fanuc) |
| Model Number | IC200ALG620 |
| Product Line | VersaMax I/O System |
| Number of Channels | 4 independent input channels |
| Conversion Resolution | 16 bits (15 bits plus sign) |
| Supported RTD Types | Platinum (25, 100, 1000 \Omega); Copper (10, 50, 100 \Omega); Nickel (100, 120 \Omega); Nickel/Iron (604 \Omega) |
| Resistance Input Ranges | 0 to 500 \Omega; 0 to 3000 \Omega |
| Wiring Configurations | 3-wire or 4-wire balanced configurations |
| Channel Update Rate | ~210 ms per channel @ 60 Hz line frequency; ~230 ms per channel @ 50 Hz |
| Base Accuracy (at 25 °C) | \pm0.15% of full scale for both temperature and resistance measurements |
| Backplane Current Draw | 125 mA maximum from 5 V DC bus; 125 mA from 3.3 V DC bus |
| Isolation Standards | 250 V AC field-side to logic; 1500 V AC field-side to frame ground (60 seconds) |
| Diagnostics Provided | Open RTD wire, input short circuit, under/over range, high/low alarms |
Field Reliability & Integration Constraints
When deploying the IC200ALG620 in process instrumentation networks, several distinct hardware and firmware constraints must be observed to avoid drift or measurement failures:
- Excitation and Self-Heating: The module automatically supplies the nominal excitation current when configured for a specific RTD type. To ensure accuracy, verify that the thermal dissipation of the sensor probe matches the process media; high excitation currents in stagnant gases can cause sensor self-heating errors.
- Lead Wire Resistance: The module compensates for lead wire resistance in 3-wire and 4-wire configurations up to a maximum of 5 \Omega per lead. For long field runs, ensure that your wire gauge limits the total single-conductor loop resistance to under 5 \Omega, and match all lead lengths identically in 3-wire topologies to maintain bridge equilibrium.
- Shield Grounding Topography: Given the 16-bit sensitivity, low-voltage RTD signals are highly susceptible to electromagnetic interference (EMI). Ground the cable shields at the source instrument whenever possible. If source grounding is unavailable, connect the shield to an auxiliary I/O terminal block mounted adjacent to the carrier, ensuring that the terminal strip has a low-impedance path to the panel frame ground.
Supply Chain & Commercial Terms
Commercial Availability Notice
- Product Condition: New Original (Factory Sealed Surplus or Current Production) / Refurbished (Tested & certified)
- Warranty Period: 12-month comprehensive warranty from the date of shipment
- Lead Time: Ships within 1 to 2 business days from active stock availability
- Pricing Structure: Listed prices are indicative and subject to current global market material costs. Contact our sales engineering team for a formal, firm quotation.
Frequently Asked Questions
Does the IC200ALG620 require a separate external 24 V DC field power supply?
No. The module derives its internal operating voltage and sensor excitation current entirely from the 5 V and 3.3 V lines on the VersaMax backplane. No external loop or field power supply needs to be wired to the carrier for the input channels to function.
Can I mix 3-wire and 4-wire RTD sensors on the same module?
Yes. Each channel is individually configured within your PLC programming software (such as Machine Edition). You can mix 3-wire platinum sensors, 4-wire copper sensors, or direct ohm inputs across the four channels on a single module without interference.
What happens to the channel data if a sensor wire breaks in the field?
The module triggers an “Open Wire” diagnostic alarm and logs the fault to the controller’s I/O Fault Table. The input data value for that specific channel will generally drive to a predetermined upper overflow value or zero, depending on your software configuration settings for fault handling.
