Choosing the right 400 watt high pressure sodium (HPS) ballast can impact lamp performance, energy efficiency, and installation ease. This article reviews five top 400W HPS ballast options suited for residential and commercial grow stations, outdoor lighting, or retrofits. Each listing covers compatibility, installation features, and reliability considerations to help you compare quickly and decide with confidence.
Summary Table
| Product | Brand | Key Benefit | Voltage Range |
|---|---|---|---|
| Compatible W/Replacement for Keystone HPS-400A-Q-KIT | Generic | Quad Tap; complete kit with mounting hardware | 120/208/240/277 |
| Philips 400w HPS Ballast Kit | PHILIPS | Multi-tap compatibility; reliable brand | 120/208/240/277/480 |
| GE 78530 GEP400TRIAC4-5 | GE | Pulse Start, trusted performance | Various 400W taps |
| Keystone Technologies HPS-400A-Q-KIT | Keystone Technologies | Quad Tap kit with all mounting hardware | 120/208/240/277 |
| iPower 400W Digital Dimmable Horticulture Ballast | iPower | Digital, dimmable; supports HPS/MH with auto bulb swap | 120/240 |
Compatible W/Replacement for Keystone HPS-400A-Q-KIT
This generic replacement kit is designed to be a quad-tap ballast solution compatible with 120/208/240/277V systems. It includes a core and coil transformer mounting bracket, capacitor, ignitor, hardware, and installation instructions. The pre-wired setup aims for quick installation and reliable operation with a 400W HPS bulb. When integrating with a Keystone or similar ballast footprint, verify the transformer mounting bracket compatibility and ensure the electrical connections align with your panel configuration.
Philips 400w HPS Ballast Kit
The Philips 400W ballast kit supports 120/208/240/277/480V inputs and is built for high-pressure sodium lamps with the S51/MI69 CWA configuration. This multi-tap design enables compatibility across different supply voltages, making it a versatile option for growing environments that require adjustable ballast configurations. The device emphasizes dependable magnetic ballast performance and straightforward installation for professionals and serious hobbyists alike.
GE 78530 GEP400TRIAC4-5 High Pressure Sodium Ballast Kit
The GE 78530 GEP400TRIAC4-5 ballast offers Pulse Start technology for improved ignition and performance with 400W HPS lamps. This 400W ballast is designed for robust operation in varying conditions and can support integral TRIAC-based control for smoother dimming and power management. GE’s reputation for reliability makes this a solid choice for growers who rely on consistent light output and long service life.
Keystone Technologies HPS-400A-Q-KIT
The Keystone HPS-400A-Q-KIT provides a complete 400W quad-tap ballast kit, including a core & coil transformer mounting bracket, capacitors, ignitor, instruction, and hardware. This kit is designed for quick installation and compatibility with multiple voltage taps, making it suitable for grow rooms or retrofit projects where a reliable, all-in-one ballast solution is preferred.
iPower 400W Digital Dimmable Horticulture Ballast
The iPower digital ballast supports dual voltage input of 120V/240V and offers dimming options at 50%, 75%, and 100%. It includes an 8-foot power cord and provides high-frequency output for reduced power loss, delivering more lumens than traditional magnetic ballasts. It also features micro-chip programming to automatically convert between HPS and MH bulbs, fast lamp ignition, and protective features such as short circuit, power surge, ignition failure, overheating, and end-of-bulb-life protection. A built-in cooling fan and fins help minimize ballast temperature for longevity.
iPower 400 Watt Horticulture Digital Dimmable Ballast
This iPower option mirrors the digital, dimmable design with dual voltage input and 50/75/100% dimming. It emphasizes fast startup and high-frequency output for efficiency gains, plus robust safety protections. The unit aims to be a versatile choice for growers needing dependable performance with flexible voltage compatibility and user-controlled light output.
TOPHORT 400 Watts Digital Dimmable Ballast
The TOPHORT ballast is a 400W digital dimmable unit compatible with HPS and MH lamps, featuring a rated input of 120V and 240V with IP65 waterproofing in some variants. It supports dimming and provides a stable high-frequency output, designed for horticultural or indoor grow installations where water resistance and adaptable input voltage are valuable.
Buying Guide: Key Considerations For 400W HPS Ballasts
- Compatibility: Check the voltage taps (120/208/240/277/480V) and confirm it matches your electrical supply and lamp configuration. Some ballasts support HPS only, while others handle MH/HPS interchangeably.
- Ignition and Start-up: Look for ballasts with reliable ignition, quick start times, and protection against ignition failure. Pulse Start technology can improve consistent arc stability.
- Electrical Protections: Overheat, short circuit, and power surge protection help extend ballast life and safeguard the grow setup. A cooling design or fan is a plus in hot environments.
- Installation: Quad-tap kits often include mounting hardware and brackets for easier installation. Pre-wired or plug-and-play configurations reduce wiring complexity.
- Longevity and Build Quality: Reputable brands with long-standing performance records (PHILIPS, GE, Keystone) tend to offer more reliable operation and better after-sales support.
- System Integration: If you plan to control lighting remotely, verify compatibility with lighting controllers or dimmers and whether the ballast supports auto bulb-type switching (HPS vs MH).
- Cost of Ownership: Compare efficiency, lamp efficacy, and heat output. Digital ballasts generally offer higher efficiency and reduced flicker, while magnetic ballasts are known for durability in certain setups.
- Warranty and Support: Review warranty duration and access to customer support for troubleshooting and replacement parts.
When selecting a 400W HPS ballast, balance voltage flexibility, installation ease, and the level of protection you require for your environment. For ongoing grow operations or retrofit projects, choosing a kit that includes mounting hardware and clear installation instructions can save time and reduce setup errors.