GE FANUC PLC VersaMax IC200MDD845D IC2OOMDD845D IC-200MDD845D

GE Fanuc IC200MDD845D | VersaMax Discrete Mixed I/O Module — 16-Pt 24V Input / 8-Pt 2A Relay Output

Mixed Discrete I/O in One VersaMax Slot

The IC200MDD845D is a mixed discrete I/O module for GE Fanuc's VersaMax modular I/O system — combining 16 digital inputs and 8 relay outputs in a single module slot. The input section provides two groups of 8 points accepting 24V DC signals in either positive logic (current-source) or negative logic (current-sink) configuration, selectable per group. The D revision introduced negative logic input capability — earlier revisions (pre-C) were positive logic only.

The output section provides 8 individually isolated Form A (normally-open) relay contacts at 2A per point. Each relay output is isolated from the others — each switches its own field load at its own circuit voltage. There are no internal fuses or snubbers on the output section. External protection must be added in the field wiring if required by the connected load type and system design.

Module status is indicated by the green OK LED, which illuminates when backplane power is present. Individual point LEDs on the module face show input and output states at a glance.

Key Specifications

Carrier and Slot Compatibility

The IC200MDD845D requires an IC200CHS series carrier base for installation — it does not mount directly to a DIN rail or panel. The carrier provides the backplane connection, field wiring terminals, and physical mounting. The module can be installed in any input or output slot of the carrier; slot position determines the module's I/O address mapping in the system configuration.

Intelligent processing is performed by the host CPU or Network Interface Unit (NIU) — the IC200MDD845D itself performs no programme execution. The CPU or NIU reads the input data and writes the output commands to this module through the backplane.

FAQ

Q1: What is the difference between the D revision (IC200MDD845D) and earlier revisions?

The D revision adds negative logic input capability for both input groups. Earlier revisions (pre-C) only supported positive logic inputs. The IC200MDD845C introduced negative logic; the D revision maintains this capability with any additional component-level updates made at that revision stage. Confirm the revision from the installed module's label if exact revision matching is required.

Q2: Are the relay outputs individually fused?

No. The IC200MDD845D has no internal output fuses or snubbers. External protection — fuses, transient voltage suppressors, or snubber circuits — must be provided in the field wiring where required by the connected load type. For inductive loads (contactors, solenoid valves), external snubbers or freewheeling diodes protect the relay contacts from voltage spikes at switch-off.

Q3: Can positive logic and negative logic inputs be mixed on the same module?

The 16 inputs are arranged in two independent groups of 8. Each group has its own common terminal, allowing one group to operate in positive logic mode and the other in negative logic mode simultaneously. This covers panels where both 2-wire and 3-wire sensor types need to connect to the same module.

Q4: What current does the IC200MDD845D draw from the backplane?

270 mA from the 5V DC backplane bus at maximum loading. The carrier's power supply budget must include this module's draw alongside all other modules in the VersaMax node. Verify total node current consumption against the carrier's rated power supply current before finalising the system configuration.

Q5: The OK LED is off. Does this mean the module has failed?

An off OK LED means backplane power is not reaching the module. Before assuming module failure, check the IC200CHS carrier's power supply and verify the module is fully seated in the carrier slot. If power is confirmed at the backplane and the OK LED remains off with the module reseated, the module has an internal power failure and requires replacement.