PHOTOBIO T 330W 100-277V S4 +10′ 120V Cord

The PHOTOBIO T 330W 100-277V S4 is a commercial-grade LED top light built by Hydrofarm for greenhouse and indoor cultivation. It delivers 858 µmol/s photon flux at 277V with a 2.6 µmol/J efficacy rating, and comes with a 10-foot 120V power cord. The slim linear housing minimizes shading in greenhouse rows, while an internal heat pipe cooling system protects the diodes for long-term reliability. DLC listed (H-3WMUH6G), it qualifies for utility rebates in most U.S. energy programs.

PHOTOBIO T 330W Specifications

All specifications below are sourced from the manufacturer product data included with this SKU (PTB3330LS41). Efficacy and photon flux figures are measured at 277V input.

Specification	Value
Wattage	330W
Photon Flux (PPF)	858 µmol/s @ 277V
Efficacy (PPE)	2.6 µmol/J @ 277V
Spectrum	S4 (full-cycle, human- and plant-compatible)
Input Voltage Range	100–277V
Included Cord	10 ft, 120V
IP Rating	IP65 (wet location rated)
Cooling System	Closed loop heat pipe
Driver Mounting	Remote-capable
DLC Listing	Yes — H-3WMUH6G (utility rebate eligible)
Weight	21.0 lb (approx.)
Supplier SKU	PTB3330LS41

Why Choose the PHOTOBIO T 330W

This fixture is aimed at commercial and semi-commercial growers who need dependable output numbers, wide voltage flexibility, and a form factor that works in both greenhouse rows and indoor grow rooms. Several design decisions set it apart from standard LED bars.

• High efficacy at commercial wattage. A 2.6 µmol/J rating at 277V places this fixture in the upper tier of 330W top lights. At 858 µmol/s photon flux, it delivers meaningful output per fixture without requiring extremely close hanging distances.
• Closed loop heat pipe cooling — no fans. The heat pipe system wicks heat away from the diodes passively. There are no moving parts to fail or bearings to wear out over time, which reduces maintenance overhead in a large commercial installation.
• S4 spectrum suits both plant and worker environments. The S4 spectrum is designed to support photosynthesis while remaining comfortable for workers who spend extended time in the growing area. This is a practical consideration in commercial greenhouse operations where staff work under the lights throughout the day.
• IP65 wet location rating. Rated for use in wet locations, this fixture can be used in high-humidity greenhouse environments or areas where overhead irrigation is present without requiring additional weatherproofing.
• DLC listing unlocks utility rebates. DLC listing (H-3WMUH6G) means this fixture qualifies for rebate programs offered by many U.S. utilities. For large installations with many fixtures, rebates can materially reduce the capital cost of a lighting upgrade.
• Remote driver mounting. The driver can be mounted away from the fixture itself, which helps manage heat in the canopy zone and gives installers flexibility in routing wiring and organizing equipment overhead.

Best Uses for the PHOTOBIO T 330W

The PHOTOBIO T 330W is suited to applications where a combination of narrow linear profile, high efficacy, and wet-rated construction matters. It is not a general-purpose grow light — it is a commercial top light designed around specific growing configurations.

• Supplemental greenhouse lighting. The slim linear design reduces shading of the plant canopy and minimizes sun interference in greenhouse rows. This makes it a practical choice for photoperiod extension and light supplementation in glass or poly greenhouses during low-light months.
• Sole-source indoor cultivation. For fully enclosed indoor rooms where no natural light is present, the 858 µmol/s output and 2.6 µmol/J efficacy support high-intensity crop production. The fixture is designed for both sole-source and supplemental use cases according to the manufacturer.
• Commercial grows pursuing utility rebates. Operations running multiple fixtures in a DLC-eligible rebate territory can use the H-3WMUH6G listing to apply for incentives. This is particularly relevant for larger greenhouse and vertical farm buildouts where rebate recovery can offset a significant portion of equipment cost.
• High-humidity or wet environments. The IP65 rating makes this fixture appropriate for growing areas where condensation, overhead irrigation mist, or high ambient humidity would rule out lower-rated fixtures.
• Installations using Autopilot PX series controllers. When paired with a compatible Autopilot PX2 or higher controller, the fixture supports precise dimming and photon output control, which is useful for matching light intensity to crop development stage or for complying with photoperiod schedules.

PHOTOBIO T 330W vs Similar LED Top Lights

The PHOTOBIO T 330W S4 sits in the mid-range commercial LED top light category. Buyers evaluating this fixture typically compare it against other 300–400W LED bars from established horticulture brands. A key point of comparison is efficacy: at 2.6 µmol/J the T 330W is competitive with other commercial fixtures in this wattage class, though specific competitors may vary in spectrum options, driver warranty, or dimming compatibility.

Compared to broad-coverage LED quantum boards or spider-style fixtures, the linear top light format of the PHOTOBIO T delivers a different light distribution pattern — narrower and more directional along the bar axis. This is a deliberate design choice for greenhouse row applications where minimizing shade cast on adjacent rows matters more than wide spread from a single fixture. For indoor grow rooms, the difference in canopy uniformity between linear bars and wider fixtures depends heavily on hanging height and row spacing, so this choice is application-specific.

If you are building a larger multi-fixture indoor room, the Gavita Pro 1700e LED is a higher-output option designed for wide-area coverage in a single fixture. The T 330W makes more sense in greenhouse row spacing or in rooms where modular fixture count is preferred over fewer high-wattage units. Consider also T5 fluorescent fixtures if the application is propagation or early vegetative stages at lower intensity.

Compatibility

The PHOTOBIO T 330W is designed with a wide operating voltage range to suit a variety of electrical infrastructure configurations found in greenhouses and commercial grow facilities.

• Voltage: The onboard driver accepts 100–277V input, making it compatible with standard North American 120V circuits as well as commercial 208V, 240V, and 277V single-phase service. The included 10-foot cord terminates in a 120V plug for immediate use on standard outlets; for operation at higher voltages, hardwiring or a different cord termination is required.
• Wet locations: IP65 rated — suitable for use in environments with water spray, high humidity, or condensation. Verify installation complies with local electrical code for wet-location fixtures.
• Controller compatibility: Photon output can be precisely controlled when paired with an Autopilot PX series controller (PX2 and above). Consult the Autopilot controller documentation for wiring and configuration details.
• Remote driver: The driver unit can be mounted remotely from the fixture head, which is useful when heat management overhead is a concern or when fixtures need to be positioned in confined spaces. Confirm cable length requirements with Hydrofarm technical documentation before designing the installation.
• Dimming and scheduling: When used with a compatible controller, the fixture supports output adjustment. Without a controller, it operates at full output for the connected voltage.

Usage Guidelines

Coverage area and hanging height recommendations are not published in the canonical product data available for this listing. The following guidance is derived from standard practice for commercial LED top lights at this output level and should be verified against Hydrofarm’s published coverage charts before finalizing your installation design.

• Hanging height — greenhouse supplemental: For supplemental greenhouse applications, the slim profile is intended to minimize shade. Mounting height is typically determined by the greenhouse structure and the crop canopy height; consult Hydrofarm installation documentation for specific guidance for your crop type.
• Hanging height — indoor sole source: For sole-source indoor use, hanging height depends on target PPFD at the canopy. At 858 µmol/s, maintain adequate distance to avoid light stress on sensitive crops. Most LED top light guides recommend starting at 18–24 inches above the canopy for vegetative growth and adjusting based on measured PPFD.
• Photoperiod control: Use a compatible timer or the Autopilot PX series controller to manage on/off cycles for photoperiod-sensitive crops. The S4 spectrum is full-cycle, so no fixture swap is needed between vegetative and flowering stages.
• Dimming: If an Autopilot PX2 or higher controller is connected, output can be reduced for seedling and propagation stages or ramped up for high-DLI flowering periods. Without a controller, the fixture runs at full output.
• Daily Light Integral (DLI) targets: Work backward from your crop’s target DLI to determine the number of hours at a given PPFD. At 858 µmol/s, actual canopy PPFD depends on hanging height, room reflectivity, and spacing between fixtures. A light meter or PAR sensor is the most reliable way to verify delivered PPFD before locking in your photoperiod schedule.

How to Install the PHOTOBIO T 330W

Installation steps below follow the standard process for commercial linear LED top lights. Refer to the Hydrofarm installation guide included with the fixture for product-specific wiring diagrams and hardware details. Always follow local electrical code and have a licensed electrician complete hardwired installations.

1. Plan the layout. Determine row spacing and fixture density based on your target PPFD and coverage area. For greenhouse supplemental applications, account for natural light levels and supplemental DLI targets before finalizing fixture count.
2. Mount hanging hardware. Install ratchet hangers, light movers, or fixed brackets at the appropriate overhead mounting points. Confirm the supporting structure can carry the fixture weight (approximately 21 lb per unit).
3. Position the fixture. Hang the fixture at the planned height above the canopy. The slim linear bar should be oriented along the row axis in greenhouse applications to minimize shading.
4. Connect power. For 120V operation, plug the included 10-foot cord into a grounded outlet on a properly rated circuit. For 208V, 240V, or 277V operation, a different cord or hardwire termination is required — do not use the included 120V cord at voltages above its rating.
5. Mount driver remotely (optional). If remote driver mounting is preferred, position the driver unit away from the fixture head in a location with adequate ventilation, and connect per the wiring diagram in the product documentation.
6. Connect controller (optional). To enable dimming and output control, connect an Autopilot PX2 or higher controller per that controller’s installation instructions. Verify compatibility and wiring before powering on.
7. Power on and verify. Switch on the fixture and confirm it illuminates. Check for any indicator light errors. Measure canopy PPFD with a PAR meter to verify output at your target hanging height and adjust height or spacing if needed.

Sources & Further Reading