As of early November 2026, Baker Hughes lists five Orbit 60 chassis types: the 3U 10-slot, 3U 19-slot, 6U 28-slot, 11-slot compact and 7-slot compact. All five platforms use the same Orbit 60 modules. That shared-module decision is what makes the expanded lineup more than a cosmetic product-line extension. A plant can standardise spares, configuration skills and engineering documentation across a small skid, a conventional 19-inch panel and a high-density 3500 retrofit, then add compact distributed nodes later without changing the module catalogue.

Bently Nevada states the intent directly: "all platforms utilize the same Orbit 60 modules for maximum flexibility and scalability." The sentence sits in the Overview of the official Orbit 60 Series product page, while the Chassis section now enumerates the five specific types. For maintenance teams and procurement, the practical question is no longer "which platform?" but "which mechanical format, and when?"

Key facts at a glance

What changed: from four form-factor descriptions to five specified chassis

The Orbit 60 page now carries two different descriptions of the chassis range, and the difference between them is the story.

The Overview paragraph still uses the earlier, looser wording: "Available in multiple chassis configurations, including the 3U-19 general-purpose, 6U double-height, 7-slot compact, and upcoming 11-slot compact (2027)". That is four form factors, with only one explicit slot count and one model flagged as future.

The Chassis section is more specific: "Chassis are available in five types: 3U 10 slot, 3U 19 slot, and 6U 28 slot, 11-slot compact, 7-slot compact." Three changes are worth flagging for anyone maintaining a specification or a bill of materials:

• A 3U 10-slot chassis is now named as a distinct type. The earlier Overview mentioned only a 3U-19 general-purpose configuration, so a smaller 3U option was not visible as a separate orderable format.
• The 6U chassis now has a published slot count. "6U double-height" was a form-factor description; "6U 28 slot" is a capacity statement. Baker Hughes also says the 6U "holds more channels than 3500 but fits in the same size cutout".
• Both compact chassis are listed side by side. Previously the 7-slot compact was listed and the 11-slot compact was described as "upcoming" for 2027. Both now appear in the five-type list, and both carry the note "Available early 2027!" in the detailed chassis bullet list.

One caution for specifiers: Baker Hughes does not publish a page-level "last updated" date on this product page, and the two sections still use different wording. Treat the five-type list as the current catalogue description, not as a dated product announcement, and confirm availability and part numbers in writing before the compact chassis become a project dependency. Our own earlier analysis of the platform, Orbit 60 vs 3500: why Bently Nevada still calls the 3500 fully supported, covers the same documentation caveat from the lifecycle side.

The five Orbit 60 chassis compared

Slot counts and availability are quoted from the Baker Hughes Orbit 60 product page. Baker Hughes does not assign applications to individual chassis; the "indicative fit" column is our engineering interpretation for planning only. A chassis designation is not the same as usable I/O capacity, because system modules such as the SIM, protection processor, condition monitoring module and power interfaces occupy positions in the rack.

One module set across five chassis: why it matters

"All platforms utilize the same Orbit 60 modules" means a chassis choice is a mechanical and capacity decision, not a new component ecosystem. Baker Hughes makes the spares argument itself on the same page under the heading "Now – Less Spares!!".

The module families that move between all five chassis are:

For a mixed fleet, the practical consequences are straightforward. A spare SIM, PPM, relay card or dynamic input module is not tied to one chassis size, so a site running a 6U main rack and smaller 3U or compact nodes can hold one spares list. Configuration is also centralised: every module in a system is configured through the single SIM, whether the system is one chassis or several bridged chassis. The 3500 architecture, by contrast, uses application-specific modules tied to a centralised rack — which is why our 3500 monitoring system catalogue is still organised by individual module part numbers such as the 3500/42M Proximitor Seismic Monitor and the 3500/22M Transient Data Interface.

Shared modules do not mean shared mechanicals. Power input arrangements, wiring termination, cooling, panel cutouts and chassis-to-chassis bridging still have to be verified per format. That distinction matters most on retrofit projects.

How the chassis is built and mounted

Orbit 60 chassis modules are inserted into the rear of the chassis, and wiring connections are also assembled from the rear. The front side of the rack carries status LEDs, connectors, the Config/Run key, a reset button and Ethernet connections. This front/back split is consistent across the range and is worth designing into cabinet layouts early: the utility side needs wiring access, while the public side needs operator and service access.

For the 19-inch chassis, Baker Hughes lists three mounting modes: EIA rail-mount, panel-cutout-mount and bulkhead mount. The 6U "double height" chassis is specifically described as holding more channels than a 3500 while fitting the same size cutout. That makes the 6U 28-slot the natural candidate when a 3500 panel is being replaced — but fitting the cutout is not the same as a drop-in swap. Wiring, terminations, module positions, configuration files and safety validation all change, as our Orbit 60 vs 3500 migration guide explains in detail.

Distributed architecture: where the smaller chassis fit

Orbit 60 is designed so that several chassis can form one system. Bridge modules interconnect chassis in linear or star topology, and Baker Hughes says this distributed approach reduces electrical installation cost, analogue ground loops and noise. A single SIM still defines the whole system — up to 80 dynamic channels — and every module is configured through it.

Read together with the five-chassis list, the architecture gives a clear deployment pattern: a larger 3U or 6U chassis hosts the main machinery train, while smaller 3U or compact nodes sit closer to remote or plantwide assets. All of them draw from the same module catalogue. This is the "Orbit Xtend" idea alongside the "Orbit conneX" and "Orbit aXess" concepts Baker Hughes introduced with the platform, and it is also where the 2027 availability of the compact chassis becomes a schedule risk rather than a technical one.

Choosing a chassis: a practical decision table

What the five-chassis lineup means for 3500 owners and spares

Nothing in the expanded chassis list retires the 3500. Baker Hughes continues to describe the 3500 line as fully supported, and the Orbit 60 6U chassis is explicitly positioned as fitting the 3500 panel cutout — a retrofit path, not a forced obsolescence programme. Most sites will run a mixed fleet for years.

That makes spares planning a two-platform exercise. Keep exact part numbers, firmware revisions and configuration backups for the installed 3500 modules that would stop production if they failed. Common holdings include the 3500/15 low-voltage DC power supply, the 3500/25 Enhanced Keyphasor Module, the 3500/33 16-channel relay module, the 3500/53 overspeed detection module and the 3500/92 Modbus communication gateway. Sensor-side spares such as 3300 XL 8 mm proximity probes and 3300 XL 11 mm Proximitor sensors remain relevant to both generations because they sit upstream of the rack.

For Orbit 60, the shared-module design should reduce the number of distinct spares lines as the platform rolls out, but the two compact chassis should not be written into a 2026 shutdown plan. If you need help matching a chassis configuration or confirming a 3500 part number before an outage, our team can check availability and cross-references, or you can browse the full Bently Nevada product catalogue.

Frequently asked questions

How many chassis configurations does Orbit 60 have?

Five. Baker Hughes states: "Chassis are available in five types: 3U 10 slot, 3U 19 slot, and 6U 28 slot, 11-slot compact, 7-slot compact."

What are the five Orbit 60 chassis types?

They are the 3U 10-slot, 3U 19-slot, 6U 28-slot, 11-slot compact and 7-slot compact chassis. The first three belong to the 19-inch chassis family (EIA rail-mount, panel-cutout-mount or bulkhead mount); the last two are compact form factors stated as available in early 2027.

Do all Orbit 60 chassis use the same modules?

Yes. Baker Hughes says "all platforms utilize the same Orbit 60 modules for maximum flexibility and scalability." The shared set includes the System Interface Module, Protection Processing Module, Condition Monitoring Module, power interface modules, Bridge and Communication Gateway modules, input modules, output modules and external displays. Chassis hardware, wiring and mounting remain format-specific.

When will the Orbit 60 compact chassis be available?

Both the 7-slot compact and the 11-slot compact carry the note "Available early 2027!" on the official Orbit 60 product page. The Overview paragraph also labels the 11-slot compact as "upcoming" for 2027. Confirm the date and orderable part numbers directly with Baker Hughes before making either a project dependency.

Does the 6U 28-slot Orbit 60 chassis fit a 3500 rack cutout?

Baker Hughes says the 6U "double height" chassis "holds more channels than 3500 but fits in the same size cutout". It is not a drop-in replacement: wiring, terminations, module positions, configuration and safety validation all differ, so a retrofit still needs a planned migration rather than a like-for-like swap.

What is the difference between the 3U 10-slot and 3U 19-slot chassis?

Both are 3U chassis in the 19-inch family, but the 10-slot version provides fewer positions while the 19-slot version is described as having "19 general purpose slots". Choose on required channel count and the positions consumed by system modules; Baker Hughes specifies one SIM per system with up to 80 dynamic channels.

Is the Bently Nevada 3500 discontinued now that Orbit 60 has more chassis options?

No. Baker Hughes continues to describe the 3500 as being in full product support, with a large installed base, and positions Orbit 60 as the platform for new installations where it is suited. A five-chassis Orbit 60 lineup broadens new-build and retrofit options; it is not an end-of-life notice for the 3500.

Where can I source 3500 and Bently Nevada spare parts?

Our 3500 monitoring system range and the wider Bently Nevada catalogue list individual modules, probes and power supplies by part number. For a mixed 3500 / Orbit 60 fleet, capture exact part numbers and firmware before ordering, because shared Orbit 60 modules do not interchange with 3500 modules.

Sources and verification note

• Baker Hughes, Bently Nevada Orbit 60 Series — Machinery Protection and Monitoring System: Overview statement on shared modules, Chassis section listing five types, 19-inch mounting options, 6U cutout statement, compact availability notes, SIM channel limit, redundant 24 Vdc inputs, module and architecture descriptions. Page content checked 4 November 2026.
• Baker Hughes, Orbit 60 Series System Datasheet (137M5182): system-level specifications and module documentation references.
• Baker Hughes, Orbit 60 Fact Sheet and compact form factors factsheet: referenced from the product page for compact chassis details.
• Baker Hughes, 3500 vs Orbit 60 comparison overview: platform positioning.
• PetroPartsOnline, Orbit 60 vs 3500: Why Bently Nevada Still Calls the 3500 Fully Supported: lifecycle, retrofit and spares context.

Verification note: the Baker Hughes product page does not publish a page-level "last updated" date, and its Overview and Chassis sections currently use different wording for the chassis range. All quoted specifications above are taken from the page as checked on 4 November 2026. Compact chassis timing is a vendor-stated target, not a confirmed ship date. Product links on this site are provided for part-number reference; confirm current availability and certifications with the manufacturer before purchase.