Bently Nevada 3500/S1-EX-01 System Monitoring Expansion Module – Extend Capacity And Integration in the 3500 Protection Rack

The Bently Nevada 3500/S1-EX-01 is designed as a system monitoring expansion module for the 3500 machinery protection platform—ideal when you need more channels, I/O flexibility, or a cleaner path to communicate condition data to control systems. It slots directly into a 3500 rack and typically works alongside existing monitor cards, relays, and interface modules without disturbing running machinery.

From my experience, plants use this type of module when they run out of capacity in a 14?slot rack or want to standardize on one rack architecture but keep options open for expansion. It seems to be a practical way to scale monitoring on compressors, turbines, or critical pumps while keeping API 670 practices in play.

• Native 3500 rack integration – Installs as a standard 3500 single-width module and uses the backplane for power and data, keeping wiring neat and consistent.

• Channel and I/O expansion – Adds capacity for additional monitoring points or auxiliary I/O, depending on the rack configuration and paired monitor cards.

• Works with existing 3500 infrastructure – Functions alongside 3500/22M TDI, 3500/92 comms gateway, relays, and monitor modules in most cases.

• Configuration via standard tools – Typically configured with the same software utilities used for the 3500 system to speed commissioning and reduce training time.

• Redundancy-friendly architecture – Supports typical 3500 redundant rack strategies so critical protection remains available during maintenance.

• Serviceable in the rack – Front-access terminals and guided module replacement help minimize downtime; hot insertion is possible when following approved 3500 procedures.

You’ll typically see the 3500/S1-EX-01 deployed in high-criticality rotating assets where channel counts grow over time:

• Refinery and petrochemical compressors, steam and gas turbines, expanders

• Pipeline booster pumps, high-speed centrifugal pumps, large fans and blowers

• Power generation balance-of-plant equipment (boiler feed pumps, ID/FD fans)

• Pulp & paper, steel, and mining critical drives where added condition points are required

A reliability engineer at a Gulf Coast plant told us they used an expansion approach like this to bring in additional 1X/2X vibration and a few temperature points without opening a second rack—kept the project under budget and within their turnaround window.

• Protect your 3500 investment – Extend an installed rack instead of commissioning a new cabinet or second rack in many cases.

• Simplify project execution – Reuse existing spare parts, wiring standards, and engineering templates; commissioning tends to be faster.

• Compatibility and lifecycle – Aligns with the mainstream 3500 ecosystem, which is widely supported and still the default in a lot of plants.

• Data accessibility – Keep a single data path to historians/CM systems through the rack’s TDI/gateway rather than scattered interfaces.

• Risk reduction – Redundant rack options and proven 3500 practices help minimize process trip risks during upgrades.

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• Cabinet and rack – Install in a clean, ventilated 19-inch cabinet. Follow 3500 rack layout guidelines; maintain airflow and clearance for module removal.

• Wiring – Use shielded, properly grounded signal cables. Keep separation from high-voltage lines. Torque terminals to spec and label points clearly.

• ESD and safety – Observe ESD precautions. If hot-swapping, follow the approved 3500 procedure; confirm alarm bypasses and plant safety rules before action.

• Commissioning – Load/verify the configuration with standard 3500 tools, validate channel OKs and alarm setpoints, and document as-built changes.

• Upkeep – Periodic visual inspection, terminal re-torque checks, and configuration backup. Firmware updates (when applicable) are best scheduled with planned outages.

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• Designed for use within the Bently Nevada 3500 platform, which carries CE and UL/cUL approvals in typical configurations

• Hazardous area suitability is achieved at the rack/system level (ATEX/IECEx in many deployments); confirm against your site classification

• Manufactured under ISO 9001 quality management systems

• Standard manufacturer warranty applies to 3500 modules; extended coverage available via service programs