GE Fanuc Output module 12/24 VDC 0.5 amps 16 points IC694MDL740 IC694MDL74O IC-694MDL740

GE Fanuc IC694MDL740 | Series 90-30 16-Point 12/24V DC Output Module — 0.5A/Point / 2A/Common / Two 8-Point Groups

16 DC Output Points in Two Independent Groups

The IC694MDL740 is a 16-point transistor output module for GE Fanuc's Series 90-30 PLC. All 16 outputs switch 12–24V DC loads, divided into two independent groups of 8 outputs sharing a common terminal each. Two separate common terminals means the two groups can be powered from different sources or switched independently — useful in panels where one group controls 24V DC loads while the other switches a different voltage or circuit.

Each output is rated for 0.5A continuous. The per-common limit of 2A caps the total simultaneous current that all eight outputs in one group can draw together — four outputs at 0.5A each, or any combination totalling 2A or less. In a cabinet with all 16 outputs driving 24V DC coil loads (contactors, solenoid valves, relays), calculate the worst-case simultaneous current per group and confirm it stays within the 2A common limit. Exceeding this causes thermal damage to the output stage even when individual points are within their per-point rating.

Key Specifications

Inrush and Load Compatibility

The 4.78A inrush rating for 10ms is the module's tolerance for the momentary surge current when switching on capacitive or motor loads. Solenoid valves and contactors produce a brief inrush when their coils first energise. The IC694MDL740 handles this inrush without damage or false overcurrent tripping, provided the inrush on any single point does not exceed 4.78A and the per-common continuous limit is observed.

The 1V maximum output voltage drop across the output transistor at rated current affects the actual voltage delivered to the load. At 24V supply with 1V drop, the load sees 23V minimum — acceptable for standard 24V DC field devices. For loads requiring tighter voltage tolerance, account for this drop in the field device selection.

FAQ

Q1: What is the maximum simultaneous current all 16 outputs can draw at once?

Each of the two groups has a 2A per-common limit. With two independent groups, the module can handle up to 4A total simultaneous output current (2A per group). In practice, this means no more than 4 outputs per group can be at their 0.5A maximum simultaneously. Calculate field load current per group before commissioning.

Q2: Can the IC694MDL740 drive 24V DC relay coils directly?

Yes. Standard 24V DC relay coils draw 50–200mA, well within the 0.5A per-point rating. Connect the coil directly to the output point and the field 24V supply common. Add a freewheeling diode across each coil if it is not included in the relay body — this suppresses the voltage spike when the output switches off and protects the output transistor.

Q3: What does the output voltage drop of 1V max mean in practice?

The output transistor has a saturation voltage of up to 1V when conducting. At 24V DC field supply with all loads on, the load receives a minimum of 23V. For most industrial field devices rated 12–24V DC, this is within their operating range. If a connected device requires the full 24V at its terminals, the supply voltage must be adjusted upward by at least 1V to compensate.

Q4: The module is rated 12–24V DC. Can both voltage levels be used simultaneously on the same module?

Yes — because the module has two independent output groups, each with its own common terminal, one group can operate from a 12V DC source while the other operates from a 24V DC source. The two groups are electrically isolated from each other at their common terminals.

Q5: What are the signs of a failing IC694MDL740 output point?

A failed output transistor on one point produces a point that is permanently off (open circuit) or permanently on (short-circuit failure). Permanently-off failure is more common. Test with the PLC in run mode and the output point forced on — if the connected load does not activate and the field supply is confirmed present at the common terminal, the output transistor has failed. At the module level, a pattern of failed points adjacent to each other can indicate a common mode fault rather than individual transistor failures.