LITHONIA LIGHTING Lithonia STACK Switch 2×2 LED Center Element
Overview
The Lithonia Lighting STACK Switch 2×2 LED Center Element Troffer (typically model series STAKS 2X2) is a versatile, high-performance, and fully switchable recessed lay-in fixture designed for commercial spaces like offices, schools, healthcare facilities, and retail environments.
As part of Lithonia’s next-generation STACK family, it combines a popular center-basket architectural aesthetic with field-adjustable flexibility.
Specifications
- Field-Adjustable Lumen Output (ALO): Features selectable lumen packages (typically 3000 LM, 4000 LM, or 5000 LM via an integrated switch module), allowing installers to customize brightness levels and adapt to various mounting heights.
- Switchable White (SWW7): Offers selectable color temperatures (3500K, 4000K, or 5000K) on the fly to fine-tune the ambiance of the space.
- Slim Profile Design: With a shallow depth of only 1.9 inches, it is exceptionally well-suited for restrictive or tight ceiling plenums.
- Volumetric Optics: Features a wide curved matte-white reflector and high-performance extruded acrylic diffusers that deliver soft, glare-free, balanced illumination across horizontal and vertical surfaces.
- Dimming: Comes standard with 0-10V dimming drivers, capable of dimming down to 10%.
- Durability & Maintenance: Rated for long life with L80 at 60,000 hours, with room-side accessible LED boards and plenum-accessible drivers.
Physical Dimensions
- Length: 23-3/4 inches
- Width: 23-3/4 inches
- Depth: 1.9 inches
- Compatibility: Fits standard 15/16-inch and narrow 9/16-inch T-grid ceiling systems.
Key Features
- Field-Adjustable Lumen Output (ALO): Integrated side-mounted switches allow selection between three distinct lumen packages (typically 3000 LM, 4000 LM, and 5000 LM).
- Switchable White (SWW7): Features a color temperature selector switch to toggle between 3500K, 4000K, and 5000K to match project requirements.
- Ultra-Low Profile: Engineered with a shallow housing depth (approximately 1.9 inches), perfect for tight ceiling plenums and restricted clearances.
- Volumetric Optics: Curved matte-white central reflector and high-performance acrylic diffusers deliver smooth, balanced, glare-free illumination.
- Standard 0-10V Dimming: Built-in driver supports smooth dimming down to 10%.
- Long Lifespan: Rated for L80 at 60,000 hours with room-side accessible LED boards and serviceable driver compartments.
Installation Instructions
Important Safety Precautions
- Disconnect Power: Always turn off grid power at the circuit breaker before beginning any electrical work or maintenance.
- Personal Protection: Wear safety glasses and protective gloves during installation.
- Compliance: All electrical connections must comply with the National Electrical Code (NEC) and local regulations.
Step-by-Step Mounting & Wiring
Configure Selectable Settings (Pre-Installation)
- Locate the dual adjustment switches on the side of the main driver enclosure.
- Set your preferred lumen output and color temperature (CCT) before installing into the ceiling, as these switches are not easily accessible post-installation. (Note: Fixtures typically ship set to maximum lumens and 4000K by default).
Mounting into T-Grid
- Maneuver the 2×2 fixture horizontally through the T-Grid ceiling framework and rest it securely onto the 15/16-inch or 9/16-inch grid runners.
- From above the ceiling, bend the integrated T-Grid safety clips outward over the grid runners on all four corners to lock the fixture firmly in place.
- Secure with independent suspension/hanger wire to the building structure if required by local codes.
Electrical Connections
Remove the electrical access plate using a screwdriver while power is off.
Connect supply wires to the fixture leads using UL-approved wire connectors:
- Black wire: Hot line-in
- White wire: Neutral line-in
- Green wire: Supply Ground
0-10V Dimming Leads: Connect Purple (0-10V +) and Pink (0-10V -) wires if low-voltage dimming is used. Otherwise, cap them off individually.
Final Closure: Reinstall the wiring access plate securely, tighten all screws, and restore power.
Troubleshooting
| Symptom | Possible Cause | Corrective Action |
| Fixture does not light up |
• Power is off or breaker is tripped. • Loose wiring connections. • Incorrect line voltage. |
• Check wall switch and circuit breaker. • Turn off power, open the wiring compartment, and verify that all wire nuts are secure and polarities match. • Verify supply voltage matches fixture label specs. |
| Dimming does not function properly |
• Incorrect wiring on 0-10V lines. • Incompatible dimmer switch. |
• Check that the purple and pink low-voltage dimming wires are properly connected to the dimmer control loop and not shorted. • Confirm the wall dimmer is a standard 0-10V sinking type. |
| Light output or color looks incorrect | • Side selector switches set differently than desired. | • Access the fixture from above the ceiling, check the driver enclosure side switches, and readjust the lumen/CCT switches to your required setting. |
| Flickering or humming |
• Loose connection. • Shared neutral issues or line interference. |
• Ensure grounding wire is properly attached. Inspect wire connectors to eliminate loose contacts. |
Documents / Resources
 | STACK Switch Driver Box |
References
- Home - DesignLightswww.designlights.org
- User Manualmanual.tools