Description
Key Technical Specifications
| Parameter | Specification |
|---|---|
| Product Model | 3500/33 149986-01 |
| Manufacturer | Bently Nevada |
| Product Family | 3500 Machinery Protection System |
| Product Type | Spare 16-Channel Relay Control Module |
| Relay Channels | 16 |
| Relay Configuration | SPDT relay architecture |
| Rack Position | Full-height front slot |
| Rack Interface | 3500 Series rack |
| Relay Logic | Programmable alarm-drive logic |
| Logic Functions | AND / OR logic and configured alarm states |
| Relay Modes | Normally Energized / Normally De-energized, configurable in groups |
| Operating Temperature | -30°C to +65°C |
| Storage Temperature | -40°C to +85°C |
| Humidity | Up to 95% non-condensing |
| Power Consumption | Approximately 5.8 W |
| Main Module Dimensions | 241 × 24.4 × 242 mm |
| I/O Module Dimensions | 241 × 24.4 × 99.1 mm |
| Main Module Weight | Approximately 0.7 kg |
| I/O Module Weight | Approximately 0.4 kg |
| Required Rack Configuration Software | Version 3.3 or later |
| Required Data Acquisition Software | Version 2.40 or later |
| Required Data Display Software | Version 1.40 or later |
| 3500/93 Compatibility | Firmware revision P or later |
| 3500/94 Compatibility | Firmware revision C or later |
| Hazardous-Area Options | CSA/NRTL/C Class I Div. 2; ATEX/IECEx/CSA Class I Zone 2, depending on system configuration |
The OEM datasheet identifies 149986-01 specifically as the spare 16-channel relay control module, while 149992-01 and related numbers identify the corresponding relay output modules.
Application Scenarios & Pain Points
A failed relay-control module can have consequences well beyond the loss of a single indication. In a turbine, compressor, pump train, or other critical machine, relay outputs may participate in alarm annunciation, permissives, shutdown commands, or external control circuits. Getting the correct module revision back into the rack matters.
- Turbomachinery protection: The 3500/33 can execute programmed relay logic based on Alert, Danger, Not-OK, and other configured 3500 system states.
- Compressor and pump trains: Multiple relay channels can be assigned to different alarm or shutdown functions, reducing the need for separate external relay logic.
- Power generation: Useful where machinery protection outputs must interface with plant shutdown, annunciation, or control circuits.
- Legacy 3500 rack maintenance: The 149986-01 is particularly relevant when an existing rack must remain in service rather than being redesigned around a newer protection platform.
Field note: Do not confuse the 149986-01 control module with the 149992-01 relay output module. They are separate pieces of the 3500/33 assembly. The OEM ordering information lists them independently.
149986-01
Related Products
- 3500/33 — The 16-channel relay module family containing the control and relay-output sections. The 149986-01 identifies the spare control module rather than the complete assembly.
- 149992-01 — Spare 16-channel relay output module. It is complementary to 149986-01 and should not be treated as the same replacement part.
- 149992-02 — Spare 16-channel failsafe relay output module. Appropriate where the installed 3500/33 configuration uses failsafe relay outputs.
- 149992-03 — Spare low-current 16-channel relay output module. Intended for applications with lower relay-current requirements.
- 149992-04 — Spare low-current 16-channel failsafe relay output module; applicable where both low-current operation and failsafe behavior are required.
- 3500/32M — 4-channel relay module family for applications requiring fewer relay outputs; it is a functional alternative only when the system’s relay-channel requirements permit the change.
- 3500/40M — 4-channel monitor module for temperature and proximity-related measurement functions; complementary to relay logic but not a relay-output replacement.
- 3500/42M — Proximity/seismic monitor used to acquire and process machinery vibration and position information; it can provide the alarm states that the 3500/33 subsequently uses for relay actions.
- 3500/15 — Power supply module for the 3500 rack. It supports the rack infrastructure but does not replace the relay-control function.
- 3500/22M — Transient Data Interface module used for rack communication and data-management functions; it is a system-level companion rather than a substitute for the 3500/33.
The Engineer’s Guide: Field Pitfalls to Avoid
Warning 1 — 149986-01 is not the complete relay-output assembly.
The OEM documentation distinguishes the 149986-01 Spare Relay Control Module from the 149992-series relay output modules. Ordering the wrong half of the assembly can leave the rack physically populated but functionally incomplete.
How to avoid it: Compare the failed module’s part number and physical location with the 3500/33 assembly before purchasing. If the requirement is for the control section, specify 149986-01 explicitly.
Warning 2 — Software revision can become the hidden compatibility problem.
The 3500/33 requires Rack Configuration Software 3.3 or later, Data Acquisition Software 2.40 or later, and Data Display Software 1.40 or later. Display-module firmware requirements also apply.
How to avoid it: Record the rack software versions before installation. If the rack has a 3500/93 or 3500/94 display, verify its firmware requirement at the same time.
Warning 3 — Do not alter relay logic without documenting the existing configuration.
The 3500/33 supports programmable alarm-drive logic, including AND/OR combinations of machinery protection states. A replacement that has not been configured correctly can produce the right LEDs but the wrong external relay action.
How to avoid it: Back up the rack configuration and document relay assignments before removing the old module. After installation, test each safety-critical relay path independently—preferably with the machine in a controlled maintenance state.
Frequently Asked Questions (FAQ)
Is Bently Nevada 3500/33 149986-01 a complete 16-channel relay module?
Not exactly. 149986-01 is the spare 16-channel relay control module associated with the 3500/33. The relay output section is separately identified by part numbers such as 149992-01. Procurement should therefore specify whether the requirement is the control module, output module, or complete 3500/33 assembly.
Can I replace 149986-01 with 149992-01?
No. They perform different functions within the 3500/33 architecture. The OEM ordering information explicitly lists 149986-01 as the spare relay control module and 149992-01 as the spare relay output module.
What software version is required for a 3500/33 installation?
The documented requirements are:
- 3500 Rack Configuration Software: Version 3.3 or later
- 3500 Data Acquisition Software: Version 2.40 or later
- 3500 Data Display Software: Version 1.40 or later
- 3500/93 LCD Display: Firmware revision P or later
- 3500/94 VGA Display: Firmware revision C or later
These requirements should be checked before commissioning a replacement module.
Can the 3500/33 be used for shutdown logic?
Yes, when correctly configured within the 3500 system. The relay logic can respond to configured machinery states and use AND/OR logic for relay activation. The exact shutdown architecture depends on the plant’s safety design, external wiring, relay configuration, and the programmed 3500 rack logic.
How should I verify a used or refurbished 149986-01?
Ask for more than a power-up photograph. At minimum, verify:
- Complete 149986-01 part number.
- Revision and serial information.
- Front-panel condition and connector condition.
- Absence of corrosion or oxidation on contacts.
- Rack communication and module-health indication.
- Configuration access through the applicable 3500 software.
- Warranty terms and documented test procedure.
For machinery protection equipment, a tested unit with traceable inspection information is preferable to an inexpensive unit whose functional history is unknown.
Can 149986-01 be installed in any 3500 rack slot?
The 3500/33 is a full-height module and its installation is governed by the 3500 rack architecture. Documentation describes the 3500/33 as being installed in a full-height position to the right of the TDI module.
Before installation, confirm the rack’s existing slot allocation, module complement, and configuration. Well, technically, physical fit is only the first check; the programmed rack configuration and relay wiring are what determine whether the replacement actually performs its intended protection function.
