Sunburst 315W CMH 120/240V w/Lamp – 4200 Kelvin

The Sunburst 315W CMH is a compact, all-in-one ceramic metal halide lighting system from Jump Start that combines a built-in digital ballast, a 95% European hammertone aluminum reflector, and a 4200K CMH lamp in a single unit. Designed for growers who want the spectral quality of CMH lighting without separate ballast and reflector components, it runs on 120V or 240V and fits small to medium indoor grow spaces.

Sunburst 315W CMH Specifications

The table below lists the key specifications for the Sunburst 315W CMH 120/240V w/Lamp – 4200 Kelvin (SKU: SBCMH31542K). All values are drawn from the manufacturer’s published product data.

Specification	Value
Brand	Jump Start
SKU	SBCMH31542K
Fixture Type	All-in-one CMH / LEC fixture
Wattage	315W
Lamp Type	Ceramic Metal Halide (CMH / LEC)
Lamp Color Temperature	4200K (lamp included)
Also Available	3100K (SKU: SBCMH31531K)
Input Voltage	120V / 240V (dual voltage)
Ballast	Built-in digital ballast
Lamp Operating Position	Horizontal
Reflector Interior Material	95% European hammertone aluminum
Cooling	Vented design
Weight	11.51 lb (5.22 kg)
Category	CMH / LEC Fixtures & Kits

Why Choose the Sunburst 315W CMH

The Sunburst CMH is designed for growers who want CMH spectral quality in a simpler, more compact package. Here is what distinguishes it from separate-component alternatives:

• All-in-one construction: The digital ballast is integrated directly into the fixture housing, eliminating the need to purchase, mount, and wire a separate ballast. This reduces setup time and keeps the installation footprint small.
• 4200K spectrum: The 4200K color temperature covers a broad-spectrum output that supports both vegetative growth and flowering, with a particular strength in the blue-to-white range useful for leafy crops and the vegetative phase of flowering plants.
• 95% European hammertone aluminum reflector: The interior reflector material is rated at 95% reflectivity and features a hammertone texture designed to scatter light evenly across the canopy, reducing hot spots and improving uniformity.
• Dual input voltage: The fixture accepts both 120V and 240V power, so it can be used with standard household circuits or upgraded 240V circuits without any hardware changes. This is useful when moving the fixture between different grow rooms or facilities.
• Vented housing: The vented design allows heat to escape from around the ballast and lamp housing, helping to manage operating temperatures in enclosed grow tents or small rooms.
• Lamp included: The 4200K CMH lamp ships with the fixture, so there is no need to source a compatible replacement lamp separately before first use.

Best Uses for the Sunburst 315W CMH

The 315W CMH power class and all-in-one format make this fixture well-suited for specific grow scenarios. The following use cases align with the product’s design and specification:

• Small to medium indoor grow tents: At 315W, this fixture is sized for tent footprints roughly in the 2×4 ft to 4×4 ft range. The compact housing keeps headroom clearance manageable in shorter tents, and the all-in-one format avoids the clutter of an external ballast inside a confined space. Growers setting up a 4×4 advance grow tent system will find this fixture a practical primary light source.
• Vegetative propagation and early-stage growth: The 4200K spectrum is commonly used during the vegetative phase for its balance of blue and white wavelengths. Growers who run a dedicated veg room or a mother-plant area benefit from the CMH arc tube’s full-spectrum output, which includes UV content that most sodium and LED sources do not produce as naturally.
• Full-cycle cultivation in single-light setups: Some cultivators run a single fixture from clone through harvest, relying on photoperiod changes rather than lamp swaps. The 4200K spectrum is neutral enough to support this approach without the need to change lamps between phases.
• Supplemental lighting alongside LED arrays: Growers running a primary LED system such as the Gavita Pro 1700e LED sometimes add a CMH fixture to introduce UV and full-spectrum content that broadens the spectral coverage in the canopy.
• Commercial propagation benches: The horizontal lamp position and even reflector diffusion make this fixture suitable for benched propagation areas where uniform coverage across a flat tray is more important than deep canopy penetration.

Compatibility

The Sunburst 315W CMH is a self-contained fixture. Because the ballast is built in, it does not connect to external digital ballasts or lighting controllers the way a DE HPS fixture would. The following compatibility notes apply:

• Power supply: The fixture accepts 120V and 240V AC input. In the US, standard 15A or 20A household circuits (NEMA 5-15 / 5-20) on 120V are compatible. On 240V, a NEMA 6-series outlet at 15A or higher is appropriate. Confirm the outlet type before plugging in.
• CMH lamps: The built-in ballast is designed specifically for 315W CMH lamps. Jump Start offers this system in two lamp variants: the 3100K version (SBCMH31531K) and this 4200K version (SBCMH31542K). Replacement lamps must be 315W CMH lamps compatible with the integrated ballast. Do not attempt to run a standard HPS or MH lamp in this fixture.
• Hanging hardware: The fixture is designed to hang overhead. Standard rope ratchet hangers are compatible with the fixture’s suspension points. Confirm the hang points and maximum load rating of your ratchet hangers before installation.
• Timers and controllers: Because the ballast is integrated, the fixture can be controlled via a standard plug-in timer on its power cord. It is not designed to connect to multi-fixture lighting controllers that communicate over a signal wire to external ballasts.
• Grow spaces: The vented design means the fixture should not be used in a sealed, airtight enclosure without airflow. In a grow tent, ensure that an inline fan is running to prevent heat buildup around the fixture. Pairing this fixture with a quality T5 fixture in a separate propagation area allows growers to stage lighting across different zones of their facility.

Usage Guidelines

The following guidelines help growers get consistent performance from the Sunburst 315W CMH:

• Hang height — vegetative phase: For the vegetative phase, a hang height of 18–24 inches above the canopy is a common starting point for a 315W CMH. Monitor plants for any light bleaching or heat stress and adjust upward if needed.
• Hang height — flowering phase: During flowering, lower the fixture to approximately 12–18 inches above the canopy if canopy temperatures allow, to increase intensity at the bud sites.
• Coverage area: A 315W CMH at typical hang heights covers roughly 9–16 square feet of canopy, depending on desired light intensity. A 3×3 ft footprint is a conservative target; a 4×4 ft footprint is achievable at moderate intensity.
• Photoperiod: For vegetative growth, run the fixture 18 hours on / 6 hours off. For flowering induction in short-day plants, switch to 12 hours on / 12 hours off. Use a plug-in timer to automate the cycle.
• Warm-up time: CMH lamps require a warm-up period after being switched on before they reach full output. Allow 3–5 minutes for the lamp to stabilize. Do not switch the lamp off and immediately back on — allow a cool-down period of at least 5 minutes before restarting.
• Lamp replacement: CMH lamps degrade over time. As a general practice, consider replacing the lamp after every 10,000–15,000 hours of use, or when output appears visibly diminished. Lamp life will vary with operating conditions.
• Horizontal position: This fixture is designed to operate with the lamp in the horizontal position. Do not mount the fixture in a way that places the lamp vertically — this can affect arc tube performance and lamp life.

How to Install the Sunburst 315W CMH

The Sunburst 315W CMH ships with the lamp pre-installed or packaged separately in protective packaging. The following steps cover a standard overhead hang installation in a grow tent or room:

1. Inspect the fixture: Before installation, inspect the reflector housing and lamp for any shipping damage. Check that the lamp is properly seated in the lamp socket and that the socket retaining hardware is secure.
2. Attach ratchet hangers: Thread a pair of ratchet hangers through the fixture’s hanging points or bail. Ensure the hangers are rated for the fixture weight (11.51 lb minimum per hanger pair).
3. Secure hanging points: Attach the other end of the ratchet hangers to a cross-bar, tent frame bar, or structural ceiling anchor. Confirm the anchor point can support the fixture weight with a safety margin.
4. Set initial hang height: Raise the fixture to approximately 24 inches above the plant canopy for initial operation. You can lower the fixture later once you have confirmed that canopy temperatures are within range.
5. Connect to power: Plug the power cord into a grounded 120V or 240V outlet appropriate for the circuit. If using a plug-in timer, plug the fixture into the timer first and set the timer to your target photoperiod before powering on.
6. Power on and verify: Switch the fixture on and observe the lamp ignition. The lamp should strike within a few seconds and reach full output within 3–5 minutes. Verify that the vents in the housing are unobstructed and that airflow is moving through the grow space.
7. Adjust hang height: After the first grow session, adjust hang height based on plant response. Signs of too-close placement include bleaching or curling of the uppermost leaves. Raise the fixture in increments of 2–3 inches until symptoms resolve.

Sources & Further Reading