Mid-Size Mid-Size

Product Overview

The ROSS Controls provides panel mounting brackets and panel nuts for ROSS Mid-Size Series filter/regulator/lubricator units. The Series enables Mid-Size FRL regulators and integrated filter/regulators to be mounted flush through a panel surface, placing the regulator adjustment knob on the front of a panel while concealing supply connections and downstream tubing behind the panel.

Three ordering configurations are available: the 876K77 complete kit (bracket and panel nut), the 875K77 bracket only, and the 877K77 panel nut only. This allows engineers and maintenance teams to order exactly the hardware needed for a new installation or a repair of an existing panel mount assembly.

The Series mounts Mid-Size Series units through a 1.56-inch (40 mm) diameter panel hole. The bracket attaches to the Mid-Size FRL body, is inserted through the panel from the rear, and the panel nut threads on from the front to clamp the assembly. Mid-Size Series units support port sizes of 1/4, 3/8, and 1/2 inch with flow capacity up to 105 scfm, making them suitable for a wide range of industrial pneumatic systems.

The Series is the correct bracket selection for the ROSS Mid-Size Series product family including Mid-Size Filters, Regulators, Lubricators, and Integrated Filter/Regulators. Engineers specifying panel-mounted air preparation for mid-range pneumatic systems will find this kit provides a secure, professional installation with minimal tooling.

Key Engineering Features

• Panel Flush-Mount Installation - Allows Mid-Size Series FRL units to be installed through a panel with the regulator knob accessible from the front and all connections accessible from behind the panel, simplifying operator interaction and protecting pneumatic connections.
• Three Ordering Options - Complete kit (876K77), bracket only (875K77), or panel nut only (877K77) reduces procurement complexity and eliminates wasted components during service or assembly.
• Compatible with Full Mid-Size FRL Product Range - Designed for all ROSS Mid-Size Series filters, regulators, lubricators, and integrated filter/regulators with 1/4, 3/8, and 1/2 inch ports.
• Standard 1.56-inch Panel Hole - Uses a 1.56-inch (40 mm) diameter panel cutout, compatible with standard pneumatic panel layout drawings and drill fixtures used for mid-size component mounting.
• Vibration-Resistant Two-Part Clamping - Bracket and panel nut clamp the FRL unit body to the panel from both sides, providing mechanically stable mounting that resists loosening under vibration from adjacent machinery.
• High Flow Capacity FRL Support - Mid-Size Series FRL units supported by this bracket deliver up to 105 scfm, making Series bracket installations suitable for high-demand pneumatic supply systems.

Technical Specifications

General Specifications

Temperature Ratings

The Series bracket hardware is compatible with all standard Mid-Size Series FRL assemblies within the Mid-Size Series operating temperature range.

Important: Temperature ratings are governed by the Mid-Size Series FRL units being mounted. Verify the FRL unit's temperature ratings for the specific application environment.

Certifications & Compliance

Typical Applications & Industries

Industrial Machine Control Panels

• Mid-Size Series regulator panel-mounted in a machine tool control enclosure for operator-accessible pressure adjustment at the 1/2 inch supply circuit, with flow delivery up to 105 scfm for multiple downstream actuators.
• Panel-mounted Mid-Size integrated filter/regulators in conveyor system control cabinets where supply air filtration and regulation are combined at a single panel-accessible location.
• Multiple Mid-Size regulators panel-mounted on a pneumatic control panel face for multi-zone pressure control in automated assembly systems.

Automotive and General Assembly

• Mid-Size filter/regulator panel-mounted on robotic welding cell supply panels where 3/8 inch port supply lines feed multiple pneumatic circuits requiring precise pressure regulation.
• Panel-mounted Mid-Size FRL in body shop pneumatic enclosures for weld gun air supply, providing filtration and regulation accessible from the panel face without opening the enclosure for adjustment.
• Replacement panel mounting hardware for Mid-Size Series FRL refurbishment on aging automotive assembly equipment without requiring full FRL unit replacement.

Packaging and Process Equipment

• Mid-Size panel-mounted filter/regulator on packaging machine supply panels for 1/4 inch actuator circuits requiring up to 105 scfm flow, with panel-face adjustment for set point changes during production line changeovers.
• Mid-Size Series regulator panel-mounted in food processing equipment where operator access to pressure adjustment must be from the outside of the equipment enclosure for hygiene and safety compliance.
• Process equipment air preparation with panel-mounted Mid-Size FRL for control of pneumatic cylinder supply at 1/2 inch ports, accessible through a lockable enclosure panel.

Test Stands and Laboratory Equipment

• Mid-Size Series filter/regulator panel-mounted on multi-circuit test stands for independent pressure control of each test circuit from the front panel, keeping all pneumatic connections behind the test stand facade.
• Air supply regulation panels with multiple panel-mounted Mid-Size regulators for calibration equipment and test fixtures requiring precise, accessible pressure set points at multiple flow rates.

Ordering and Model Number Configuration

The Series Mid-Size Bracket Kit is offered in three configurations. Order the complete 876K77 kit for new panel mount installations; order bracket (875K77) or panel nut (877K77) individually for replacement parts.

Order 876K77 for new panel mount installations of Mid-Size Series FRL units - includes both bracket (875K77) and panel nut (877K77).

Order 875K77 bracket only for replacement when the panel nut is intact and only the bracket requires replacement.

Order 877K77 panel nut only for replacement when the bracket is retained and only the panel nut requires replacement.

Panel hole must be drilled to exactly 1.56 inches (40 mm) diameter before installation.

One Series kit mounts one Mid-Size Series FRL unit. Order one kit per unit for new panel assemblies.

For MD3 Series units (larger modular style), use the R-A127-11 panel mounting kit and R-127-11 panel nut instead of the series.

Accessories

Complete Mid-Size FRL Bracket Kit Family

Order complete kit or individual components.

Panel Mounting Kits for Other FRL Sizes

Companion bracket kits for other ROSS FRL series sizes.

Related Products & Accessories

• Mid-Size Series FRL Products - ROSS Mid-Size Series filters, regulators, lubricators, and integrated filter/regulators for 1/4, 3/8, and 1/2 inch ports, flow to 105 scfm. https://www.rosscontrols.com/en/categories/59-frl-accessories
• 166 Series Miniature Bracket Kit - Panel mounting bracket and panel nut kit for Miniature Series FRL units with 1.19-inch panel hole. https://www.rosscontrols.com/en/series/166-miniature
• 162 Series Full-Size Bracket Kit - Panel mounting bracket and panel nut kit for Full-Size and MD4 Series FRL units. https://www.rosscontrols.com/en/series/162-full-size
• 169 Series Mid-Size and Full-Size Bracket Assembly Kit - Connector kit for joining Mid-Size and Full-Size modular FRL units to one another. https://www.rosscontrols.com/en/series/169-mid-size-full-size
• 172 Series Port Blocks - Female port blocks for connecting Mid-Size and Full-Size FRL assemblies to 1/4 to 3/4 inch supply and downstream piping. https://www.rosscontrols.com/en/series/172-mid-size-full-size

Frequently Asked Questions (FAQ)

Q: What is included in the 876K77 complete kit?

A: The 876K77 kit includes one 875K77 bracket and one 877K77 panel nut, providing everything needed to panel-mount one Mid-Size Series FRL regulator or integrated filter/regulator.

Q: What panel hole size is required for the series?

A: The Series requires a 1.56-inch (40 mm) diameter circular panel hole. This is slightly larger than the Miniature Series hole (1.19 in / 30 mm) to accommodate the larger Mid-Size FRL body diameter.

Q: Does the series work with MD3 Series FRL units?

A: No. MD3 Series units are larger modular units that require the R-A127-11 panel mounting kit with a 2.06-inch (52 mm) panel hole. The Series (876K77) is sized for the standard Mid-Size Series and will not properly mount MD3 Series units.

Q: Can the bracket and panel nut be ordered separately for service?

A: Yes. The 875K77 bracket and 877K77 panel nut are available individually for replacement during service. Order the component that requires replacement without purchasing a complete kit.

Q: Is the series suitable for stainless steel panels?

A: Yes. The bracket and panel nut hardware is designed for use with standard metal panel materials including carbon steel, stainless steel, and aluminum. Panel thickness compatibility should be verified against the dimensional drawings in the ROSS FRL catalog.

Q: Can a Mid-Size FRL unit with a metal bowl be panel-mounted with the series?

A: Yes, the series brackets attach to the FRL body and are independent of bowl type. Metal bowl and polycarbonate bowl Mid-Size units use the same bracket kit.

Q: What is the maximum panel thickness for the series?

A: Consult the dimensional drawings in the ROSS FRL catalog for panel thickness specifications. The catalog drawing shows the engagement length between bracket and panel nut, which determines the range of panel thicknesses that can be accommodated.

Q: Is there a torque specification for tightening the panel nut?

A: No specific torque value is published. Tighten the 877K77 panel nut to firm contact with the panel face using a wrench. The goal is to prevent rotation of the FRL unit in the panel hole during operation; overtightening is not beneficial and may damage the panel material.

Q: Can multiple Series bracket assemblies be mounted side by side?

A: Yes, subject to the lateral clearance between FRL units at the specified panel hole centers. Consult Mid-Size FRL dimensional data to determine minimum center-to-center spacing for adjacent panel-mounted units.

Q: Is there a version for G (BSPP) thread Mid-Size units?

A: The Series bracket kit attaches to the FRL unit body, not the threaded ports, so the same bracket works for both NPT and G (BSPP) thread Mid-Size Series FRL units.

Q: What other accessories are needed for a complete Mid-Size FRL panel installation?

A: For a complete panel-mounted Mid-Size FRL installation, you will typically need: Series bracket kit (876K77), Mid-Size FRL unit (filter, regulator, lubricator, or combined), connector kit (892K77) if connecting modular units, and female port blocks (893K77 to 896K77) for piping connections.

Q: Where can I get technical drawings for the series?

A: Dimensional drawings for the series bracket system are published in the ROSS FRL catalog (Form A10120), available for download at rosscontrols.com. Contact ROSS Controls at (800) 438-7677 for additional documentation.

Installation & Maintenance Guidelines

• Mark and drill a clean 1.56-inch (40 mm) diameter hole in the mounting panel. Deburr all edges to ensure flat bracket contact.
• Attach the 875K77 bracket to the Mid-Size Series FRL unit body following the orientation specified in the ROSS FRL catalog for the specific FRL model being installed.
• Insert the bracketed FRL unit through the panel hole from the rear (inside the enclosure) until the bracket shoulder contacts the rear face of the panel.
• Thread the 877K77 panel nut onto the bracket from the front of the panel by hand until snug.
• Tighten the panel nut with a wrench to clamp the FRL unit to the panel. Verify the unit does not rotate in the panel hole.
• Connect supply inlet and downstream outlet piping to the FRL ports from behind the panel.
• Pressurize the system and check all connections for leaks before placing in service.
• Set the regulator outlet pressure using the front-panel adjustment knob to the desired operating pressure.

Warranty & Global Support

ROSS Controls provides a one-year warranty on all products, covering defects in material and workmanship from date of purchase.

Global technical support is available through ROSS offices in the USA (headquarters in Ferndale, Michigan), Canada, Brazil, Germany, France, United Kingdom, India, China, and Japan.

Contact ROSS Controls USA at (800) 438-7677 or visit rosscontrols.com for product configuration, technical support, and distributor locator services.

For the complete Mid-Size Series FRL accessory catalog, dimensional drawings, and installation instructions, visit rosscontrols.com or contact ROSS Controls at (800) 438-7677.

Download Catalog: https://www.rosscontrols.com/en/series/167-mid-size