Chief CMA347

The Chief CMA347 is a patented vibration isolating coupler designed for large venue projector installations where building vibration compromises image quality. It inserts between two 1.5" NPT extension columns in a Chief CMS-series pipe run and absorbs the mechanical energy — caused by HVAC systems, foot traffic, road traffic or slamming doors — before it reaches the projector. The CMA347 comes with two interchangeable spring sets to accommodate system weights from 0 to 15,9 kg, making it compatible with a wide range of projector and mount combinations. Finished in black steel, it is ceiling-capable and engineered to integrate seamlessly into existing Chief column assemblies without requiring modifications to the surrounding infrastructure.

Patented Vibration Isolation Between Columns

The CMA347 installs inline between two 1.5" NPT extension columns and absorbs vibration energy above the connection point before it travels down to the projector. Building vibration from HVAC systems, foot traffic, road traffic and closing doors is a persistent problem in large venues — even small oscillations translate to visible image movement on a big screen, which is disruptive in conference rooms, auditoriums and houses of worship. By intercepting vibration at the column joint rather than relying on the projector mount alone, the CMA347 eliminates image shake at the source. The result is a stable, sharp picture throughout the entire day, without any active electronics or ongoing maintenance.

Two Spring Sets for Flexible Load Ranges

The coupler ships with two different spring configurations, covering system weights of 0–6,8 kg and 6,8–15,9 kg (maximum 15,9 kg total load below the isolator — including column, mount and projector). Being able to select the correct spring rate is critical: an under-loaded spring does not tension properly and allows unwanted movement, while an over-loaded spring cannot compress and passes vibration through. Having both sets in the box means the correct spring can be fitted at installation without a separate order, saving a return visit. Common mount weights to factor in: Chief RPAU ≈ 1,8 kg, RPMAU ≈ 2,3 kg.

Sharp image all day. No vibration. No electronics.

Full Legrand Chief MFG USA warranty included

Universal 1.5" NPT Compatibility

The CMA347 uses the industry-standard 1.5" NPT threaded pipe connection, which means it is compatible with any manufacturer's 1.5" NPT extension column — not just Chief's own CMS series. This makes it a straightforward retrofit for existing column-based ceiling systems: the coupler simply threads in between two pipe sections without requiring new brackets, adaptors or structural changes. For integrators working across mixed or legacy installations, this broad compatibility removes any guesswork about fit and allows the vibration isolator to be specified confidently on virtually any large-venue pipe-drop project.