Description
Product Overview
The Schneider Electric Modicon AS-B836-016 is a 16-point isolated DC output module designed for Modicon 984 programmable logic controller systems and the associated 800-Series I/O architecture. It provides discrete output switching for industrial control applications requiring DC field voltage across a wide operating range. The documented operating voltage is 12–250 VDC, making this module suitable for legacy control installations using different DC voltage levels. Each of its 16 output points is assigned to a separate group, with one output per group. This arrangement provides point-level isolation rather than combining multiple output points into a shared output group.
The AS-B836-016 has different current ratings depending on the field voltage. Its typical maximum current per point is 0.75 A at 250 VDC, 1 A at 125 VDC, and 1.5 A at 48 VDC. The maximum total module current is 8 A. The specified maximum response times are 1 ms from OFF to ON and 5 ms from ON to OFF. These characteristics are important when evaluating relay or solenoid switching loads, output timing, and the electrical requirements of existing field devices. The module also has a maximum leakage current of 1 mA at 12 VDC and a specified surge current of 5 A for 10 ms at a one-second repetition interval.
For maintenance teams working with older Modicon installations, the Schneider AS-B836-016 requires careful attention to its terminal assembly and housing configuration. The specified terminal connector is AS-8535-000, and the module occupies one I/O slot. It is discontinued, so replacement procurement should include a review of terminal wiring, mechanical keying, output voltage, load current, and module condition. A similar-looking 16-point output module is not necessarily electrically equivalent. Confirm the exact PLC rack and field wiring before installation.
Product Introduction (Non-Templated)
A failed DC output channel can interrupt a machine sequence even when the PLC processor and input circuits remain operational. On older Modicon 984 systems, replacing the output module requires more than matching the 16-point count. The field voltage, point isolation, current rating, and terminal connector must also match the installed circuit.
The AS-B836-016 is a high-voltage-range DC output module, not a standard 24 VDC transistor output card. Its 12–250 VDC operating range and voltage-dependent current limits should be checked against the connected loads before approving a replacement.
Key Technical Specifications
| Parameter | Specification |
|---|---|
| Product Model | AS-B836-016 |
| Manufacturer | Schneider Electric / Modicon |
| Product Family | 800-Series I/O |
| PLC Platform | Modicon 984 |
| Product Type | Isolated DC digital output module |
| Number of Outputs | 16 points |
| Output Voltage Range | 12–250 VDC |
| Number of Output Groups | 16 |
| Outputs per Group | 1 |
| Isolation | Individually isolated outputs, as specified by module configuration |
| Maximum Current at 250 VDC | 0.75 A typical per point |
| Maximum Current at 125 VDC | 1 A typical per point |
| Maximum Current at 48 VDC | 1.5 A typical per point |
| Maximum Module Current | 8 A |
| Leakage Current | 1 mA maximum at 12 VDC |
| Surge Current | 5 A for 10 ms, once per second |
| OFF-to-ON Response | 1 ms maximum |
| ON-to-OFF Response | 5 ms maximum |
| Backplane +5 V Consumption | 50 mA |
| Backplane +4.3 V Consumption | 603 mA |
| Backplane -5 V Consumption | 0 mA |
| Slot Requirement | 1 slot |
| Weight | 1.16 kg (2.55 lb) |
| Terminal Connector | AS-8535-000 |
| Fusing | One fuse per group |
| Operating Temperature | Verify against applicable installation documentation |
| Mounting | Modicon 800-Series housing / backplane |
The current ratings above are voltage-dependent typical maximum values, not a universal per-point rating. Do not apply the 1.5 A figure to a 250 VDC load.
AS-B836-016
Major Features and Advantages
Wide DC operating voltage range
The 12–250 VDC output range supports legacy control circuits operating at different DC voltage levels. This makes correct field-voltage identification essential before installation.
Sixteen isolated output points
The module provides 16 output points, each assigned to its own group. This configuration helps separate individual field circuits and limits the direct electrical interaction between output channels.
Voltage-dependent current capacity
The module supports different current limits according to the applied DC voltage: 0.75 A at 250 VDC, 1 A at 125 VDC, and 1.5 A at 48 VDC. Load selection must account for these differences.
Fast output response
The specified response times are 1 ms OFF-to-ON and 5 ms ON-to-OFF. These values are relevant to sequence timing and control logic, although actual field-device response may be slower.
Individual group fusing
The module documentation specifies one fuse per output group. Fuse condition and correct replacement ratings should be checked during troubleshooting. Do not bypass protective fusing to restore operation.
Single-slot installation
The AS-B836-016 occupies one slot in the Modicon 800-Series I/O arrangement. Correct mechanical keying and terminal connector selection remain important during replacement.
Legacy Modicon system support
For existing 984 installations, retaining the original module type can reduce the scope of a control-system modification. Since the module is discontinued, inspection and functional testing are important procurement steps.
Related Products
- AS-B837-016 – 16-point 24 VAC/DC digital input module; different I/O function.
- AS-B833-016 – 16-point 24 VDC input module for Modicon 800-Series systems.
- AS-B832-016 – 16-point 24 VDC output module.
- AS-B838-032 – 32-point DC output module with a different channel configuration.
- AS-B840-008 – Modicon 800-Series output module with a different output arrangement.
- AS-8535-000 – Terminal connector specified for the AS-.
- AS- – Original 16-point isolated DC output module.
These products belong to the broader Modicon 800-Series family, but their electrical functions and terminal arrangements differ. Do not treat them as direct replacements without a compatibility review.
Frequently Asked Questions
Q1: What is the Schneider Electric AS- used for?
It is a 16-point isolated DC output module used in Modicon 984 and 800-Series PLC installations. It switches DC field circuits according to the PLC control program.
Q2: Is the AS- a standard 24 VDC output module?
No. Its documented operating range is 12–250 VDC. It should not be confused with output modules designed specifically for 24 VDC applications.
Q3: Can the AS- switch 250 VDC loads?
Yes, the module is specified for operation up to 250 VDC. The typical maximum current at that voltage is 0.75 A per output point. Confirm the load’s steady-state and inrush requirements before connection.
Q4: Can I hot-swap the AS-?
Do not assume hot-swap capability. Follow the Modicon 984 system maintenance procedure, isolate field power as required, and verify whether the installed rack configuration permits energized module removal.
Q5: Does the AS- support firmware v3.1?
This is an I/O hardware module, not a standalone processor with independent application firmware. Compatibility is determined by the PLC platform, rack configuration, and system documentation rather than a generic firmware v3.1 designation.
Q6: Which terminal connector is required for the AS-?
The documented terminal connector is AS-8535-000. Confirm the connector’s condition, terminal numbering, wiring, and mechanical keying before transferring field connections.
Chapter 3
Q7: Is the AS- still manufactured?
Available product records identify it as discontinued by the manufacturer. Replacement procurement should include condition verification and a functional test rather than relying on the model label alone.
Procurement and Quality Control Notes
The AS- is a legacy high-voltage DC output module. The main procurement risk is receiving a module with damaged output circuitry, incorrect terminal hardware, or an incompatible mechanical configuration.
Before shipment, request:
- Clear photographs of the complete module and nameplate.
- Confirmation of the exact AS- model.
- Inspection of the terminal connector AS-8535-000.
- Visual inspection of housing keying and backplane contacts.
- Output testing across representative channels.
- Verification of output isolation and leakage characteristics.
- Confirmation of fuse condition and correct fuse ratings.
- Written condition classification: new, unused, refurbished, or used.
- Warranty terms and return conditions.
Engineering recommendation: Match the replacement to the existing DC field voltage and actual load current. The AS- has voltage-dependent output ratings; treating it as a generic 24 VDC output card can result in an incorrect replacement decision.
