{"product_id":"lumatek-400w-digital-ballast","title":"Lumatek 400W Digital Ballast by Lumatek — Dimmable HPS \u0026 MH Grow Light Ballast","description":"\u003cdiv style=\"font-family: 'Helvetica Neue', Arial, sans-serif; max-width: 860px; margin: 0 auto; color: #1a1a1a;\"\u003e\n\n\u003cp style=\"font-size: 1.05rem; line-height: 1.7; margin-bottom: 1.5rem;\"\u003eThe Lumatek 400W Digital Ballast (LK4240) runs both HPS and MH lamps on a standard 240V circuit, with dimmable output for 250W and 400W globes plus a Super Lumens switch that pushes roughly 10% more output from your lamp when you want it. Compared to an old magnetic ballast you get up to 30% more lumens, silent fanless operation and far less waste heat — the sensible upgrade for any single-lamp HID setup.\u003c\/p\u003e\n\n\u003cdiv style=\"display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 1rem; margin-bottom: 2rem;\"\u003e\n\u003cdiv style=\"background: #f4f9f4; border-left: 4px solid #2e5e2e; padding: 1rem 1.2rem; border-radius: 6px;\"\u003e\n\u003cstrong style=\"display: block; margin-bottom: 0.3rem; color: #2e5e2e;\"\u003eUp to 30% More Lumens\u003c\/strong\u003e\u003cspan style=\"font-size: 0.9rem; color: #444;\"\u003eDigital switching electronics drive the lamp harder and more efficiently than magnetic ballasts, so more of your power bill ends up as light.\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"background: #f4f9f4; border-left: 4px solid #2e5e2e; padding: 1rem 1.2rem; border-radius: 6px;\"\u003e\n\u003cstrong style=\"display: block; margin-bottom: 0.3rem; color: #2e5e2e;\"\u003eDimmable + Super Lumens\u003c\/strong\u003e\u003cspan style=\"font-size: 0.9rem; color: #444;\"\u003eRun a 250W or 400W lamp from the one unit, then flick the Super Lumens switch for around 10% extra output in peak flower.\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"background: #f4f9f4; border-left: 4px solid #2e5e2e; padding: 1rem 1.2rem; border-radius: 6px;\"\u003e\n\u003cstrong style=\"display: block; margin-bottom: 0.3rem; color: #2e5e2e;\"\u003eSilent, Fanless Cooling\u003c\/strong\u003e\u003cspan style=\"font-size: 0.9rem; color: #444;\"\u003eA graduated fin housing sheds heat passively — no fan, no hum, no vibration. Rubber feet keep air moving underneath.\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"background: #f4f9f4; border-left: 4px solid #2e5e2e; padding: 1rem 1.2rem; border-radius: 6px;\"\u003e\n\u003cstrong style=\"display: block; margin-bottom: 0.3rem; color: #2e5e2e;\"\u003eBuilt to Last\u003c\/strong\u003e\u003cspan style=\"font-size: 0.9rem; color: #444;\"\u003eInternal RF shielding, resin-coated components and an external breaker that protects against power surges, backed by a 3-year warranty.\u003c\/span\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003ch2 style=\"font-size: 1.1rem; font-weight: 700; border-bottom: 2px solid #2e5e2e; padding-bottom: 0.4rem; margin-bottom: 1rem;\"\u003eSpecifications\u003c\/h2\u003e\n\u003cdiv style=\"display: grid; grid-template-columns: 1fr 1fr; gap: 0.5rem 2rem; margin-bottom: 2rem; font-size: 0.95rem;\"\u003e\n\u003cdiv\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e LK4240\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cstrong\u003eInput:\u003c\/strong\u003e 240V, 50\/60Hz\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cstrong\u003eInput current:\u003c\/strong\u003e 1.75A\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cstrong\u003eLamp compatibility:\u003c\/strong\u003e 400W HPS \u0026amp; MH\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cstrong\u003eOutput settings:\u003c\/strong\u003e 250W \/ 400W + Super Lumens\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cstrong\u003eCooling:\u003c\/strong\u003e Passive graduated fin, fanless\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cstrong\u003eWiring:\u003c\/strong\u003e Prewired with lamp cord\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 3 years\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003cdiv style=\"background: #fff8e1; border-left: 4px solid #f9a825; padding: 1rem 1.3rem; border-radius: 6px; margin-bottom: 2rem;\"\u003e\n\u003cstrong style=\"color: #e65100; display: block; margin-bottom: 0.5rem;\"\u003eGrow Guys Tip\u003c\/strong\u003e\n\u003cul style=\"margin: 0 0 0 1.2rem; padding: 0; font-size: 0.93rem; line-height: 1.7;\"\u003e\n\u003cli\u003eOnly engage the Super Lumens switch on HPS lamps — Lumatek advises against using it with MH globes.\u003c\/li\u003e\n\u003cli\u003eAlways match the output setting to your lamp. Never run a 250W globe on the 400W setting.\u003c\/li\u003e\n\u003cli\u003eMount the ballast off the floor with airflow around the fins — cooler electronics last longer.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003ch2 style=\"font-size: 1.1rem; font-weight: 700; border-bottom: 2px solid #2e5e2e; padding-bottom: 0.4rem; margin-bottom: 1rem;\"\u003eGetting Set Up\u003c\/h2\u003e\n\u003cdiv style=\"margin-bottom: 2rem;\"\u003e\n\u003cdiv style=\"display: flex; align-items: flex-start; gap: 14px; padding: 12px 0; border-bottom: 1px solid #edf3ed; font-size: 0.93rem; line-height: 1.6;\"\u003e\n\u003cspan style=\"background: #2e5e2e; color: #fff; font-weight: 700; font-size: 0.85rem; min-width: 28px; height: 28px; border-radius: 50%; display: flex; align-items: center; justify-content: center; flex-shrink: 0; margin-top: 1px;\"\u003e1\u003c\/span\u003e\u003cspan\u003eMount the ballast in a dry spot with clear airflow, away from direct heat from your lamp.\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display: flex; align-items: flex-start; gap: 14px; padding: 12px 0; border-bottom: 1px solid #edf3ed; font-size: 0.93rem; line-height: 1.6;\"\u003e\n\u003cspan style=\"background: #2e5e2e; color: #fff; font-weight: 700; font-size: 0.85rem; min-width: 28px; height: 28px; border-radius: 50%; display: flex; align-items: center; justify-content: center; flex-shrink: 0; margin-top: 1px;\"\u003e2\u003c\/span\u003e\u003cspan\u003eConnect the prewired lamp cord to your reflector, and screw your HPS or MH globe in firmly.\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display: flex; align-items: flex-start; gap: 14px; padding: 12px 0; border-bottom: 1px solid #edf3ed; font-size: 0.93rem; line-height: 1.6;\"\u003e\n\u003cspan style=\"background: #2e5e2e; color: #fff; font-weight: 700; font-size: 0.85rem; min-width: 28px; height: 28px; border-radius: 50%; display: flex; align-items: center; justify-content: center; flex-shrink: 0; margin-top: 1px;\"\u003e3\u003c\/span\u003e\u003cspan\u003eSet the output to match your lamp wattage before powering on.\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display: flex; align-items: flex-start; gap: 14px; padding: 12px 0; font-size: 0.93rem; line-height: 1.6;\"\u003e\n\u003cspan style=\"background: #2e5e2e; color: #fff; font-weight: 700; font-size: 0.85rem; min-width: 28px; height: 28px; border-radius: 50%; display: flex; align-items: center; justify-content: center; flex-shrink: 0; margin-top: 1px;\"\u003e4\u003c\/span\u003e\u003cspan\u003ePlug into 240V mains and switch on. Once the lamp is fully warmed, engage Super Lumens on an HPS globe if you want the extra output.\u003c\/span\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003ch2 style=\"font-size: 1.1rem; font-weight: 700; border-bottom: 2px solid #2e5e2e; padding-bottom: 0.4rem; margin-bottom: 1rem;\"\u003ePairs Well With\u003c\/h2\u003e\n\u003cdiv style=\"display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 1rem; margin-bottom: 2rem;\"\u003e\n\u003ca href=\"\/collections\/grow-globes\" style=\"text-decoration: none; color: inherit; background: #f4f9f4; border: 1px solid #c8dfc8; padding: 1rem; border-radius: 6px; display: block;\"\u003e\u003cstrong style=\"color: #2e5e2e; display: block; margin-bottom: 0.3rem;\"\u003eGrow Light Globes\u003c\/strong\u003e\u003cp style=\"font-size: 0.85rem; margin: 0;\"\u003ePair with a quality 400W HPS for flower or MH for veg.\u003c\/p\u003e\u003c\/a\u003e\n\u003ca href=\"\/collections\/hid-grow-lighting\" style=\"text-decoration: none; color: inherit; background: #f4f9f4; border: 1px solid #c8dfc8; padding: 1rem; border-radius: 6px; display: block;\"\u003e\u003cstrong style=\"color: #2e5e2e; display: block; margin-bottom: 0.3rem;\"\u003eHID Grow Lights\u003c\/strong\u003e\u003cp style=\"font-size: 0.85rem; margin: 0;\"\u003eReflectors and shades to put every lumen on your canopy.\u003c\/p\u003e\u003c\/a\u003e\n\u003ca href=\"\/collections\/lumatek\" style=\"text-decoration: none; color: inherit; background: #f4f9f4; border: 1px solid #c8dfc8; padding: 1rem; border-radius: 6px; display: block;\"\u003e\u003cstrong style=\"color: #2e5e2e; display: block; margin-bottom: 0.3rem;\"\u003eMore From Lumatek\u003c\/strong\u003e\u003cp style=\"font-size: 0.85rem; margin: 0;\"\u003eLamps, controllers and gear from the digital ballast specialists.\u003c\/p\u003e\u003c\/a\u003e\n\u003c\/div\u003e\n\n\u003ch2 style=\"font-size: 1.1rem; font-weight: 700; border-bottom: 2px solid #2e5e2e; padding-bottom: 0.4rem; margin-bottom: 1rem;\"\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cdetails style=\"margin-bottom: 0.8rem; border: 1px solid #e0e0e0; border-radius: 6px; padding: 0.8rem 1rem;\"\u003e\u003csummary style=\"font-weight: 600; cursor: pointer;\"\u003eDoes this ballast run both HPS and MH lamps?\u003c\/summary\u003e\u003cp style=\"margin: 0.6rem 0 0; font-size: 0.93rem; line-height: 1.6;\"\u003eYes. The LK4240 runs both high pressure sodium and metal halide lamps, so you can use MH for veg and swap to HPS for flower on the same ballast.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails style=\"margin-bottom: 0.8rem; border: 1px solid #e0e0e0; border-radius: 6px; padding: 0.8rem 1rem;\"\u003e\u003csummary style=\"font-weight: 600; cursor: pointer;\"\u003eCan I use the Super Lumens switch with a metal halide globe?\u003c\/summary\u003e\u003cp style=\"margin: 0.6rem 0 0; font-size: 0.93rem; line-height: 1.6;\"\u003eNo. Lumatek advises the Super Lumens boost is for HPS lamps only. Run MH globes at their rated setting.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails style=\"margin-bottom: 0.8rem; border: 1px solid #e0e0e0; border-radius: 6px; padding: 0.8rem 1rem;\"\u003e\u003csummary style=\"font-weight: 600; cursor: pointer;\"\u003eIs it noisy?\u003c\/summary\u003e\u003cp style=\"margin: 0.6rem 0 0; font-size: 0.93rem; line-height: 1.6;\"\u003eNo. There is no fan and no magnetic hum — the graduated fin housing cools the unit passively, so it runs silent.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails style=\"margin-bottom: 0.8rem; border: 1px solid #e0e0e0; border-radius: 6px; padding: 0.8rem 1rem;\"\u003e\u003csummary style=\"font-weight: 600; cursor: pointer;\"\u003eWill it work on a normal Australian power point?\u003c\/summary\u003e\u003cp style=\"margin: 0.6rem 0 0; font-size: 0.93rem; line-height: 1.6;\"\u003eYes. It is a 240V, 50\/60Hz unit drawing 1.75A, so it plugs into a standard Australian outlet.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails style=\"margin-bottom: 0.8rem; border: 1px solid #e0e0e0; border-radius: 6px; padding: 0.8rem 1rem;\"\u003e\u003csummary style=\"font-weight: 600; cursor: pointer;\"\u003eWhat warranty does it carry?\u003c\/summary\u003e\u003cp style=\"margin: 0.6rem 0 0; font-size: 0.93rem; line-height: 1.6;\"\u003eThis model carries a 3-year full warranty from Lumatek, with resin-coated internals and an external breaker protecting it against power surges.\u003c\/p\u003e\u003c\/details\u003e\n\n\u003cdiv style=\"background: #1c3a1c; color: #fff; padding: 2rem; border-radius: 10px; text-align: center; margin-top: 2rem;\"\u003e\n\u003ch2 style=\"color: #fff !important; margin: 0 0 0.5rem; font-size: 1.3rem;\"\u003eRun Your HID Lamps the Smart Way\u003c\/h2\u003e\n\u003cp style=\"color: #aed1ae !important; margin: 0 0 1.5rem; font-size: 0.95rem;\"\u003eMore light, less heat, no noise. Free shipping over $499*.\u003c\/p\u003e\n\u003cdiv style=\"display: flex; justify-content: center; gap: 1rem; flex-wrap: wrap;\"\u003e\n\u003cbutton id=\"btn-add-to-cart\" style=\"background: #b67317 !important; color: #fff !important; padding: 0.85rem 2rem !important; border: none !important; border-radius: 6px !important; font-size: 1rem !important; font-weight: 700 !important; cursor: pointer !important;\"\u003eAdd to Cart\u003c\/button\u003e\n\u003ca href=\"\/collections\/grow-lighting\" style=\"background: transparent !important; color: #fff !important; padding: 0.85rem 2rem !important; border: 2px solid #fff !important; border-radius: 6px !important; font-size: 1rem !important; font-weight: 600 !important; text-decoration: none !important; display: inline-block !important;\"\u003eShop Grow Lighting\u003c\/a\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003cscript\u003e\ndocument.addEventListener('DOMContentLoaded', function() {\n  var btn = document.getElementById('btn-add-to-cart');\n  if (!btn) return;\n  btn.addEventListener('click', function() {\n    fetch('\/cart\/add.js', {\n      method: 'POST',\n      headers: {'Content-Type': 'application\/json'},\n      body: JSON.stringify({id: parseInt('52071525187882', 10), quantity: 1})\n    }).then(function(response) {\n      return response.json();\n    }).then(function(data) {\n      if (data.status \u0026\u0026 data.status !== 200) { throw new Error(data.description); }\n      btn.textContent = 'Added to Cart';\n      btn.style.background = '#2e5e2e';\n      setTimeout(function() {\n        btn.textContent = 'Add to Cart';\n        btn.style.background = '#b67317';\n      }, 2000);\n    }).catch(function() {\n      btn.textContent = 'Error — Try Again';\n      btn.style.background = '#c0392b';\n      setTimeout(function() {\n        btn.textContent = 'Add to Cart';\n        btn.style.background = '#b67317';\n      }, 2500);\n    });\n  });\n});\n\u003c\/script\u003e\n\n\u003c\/div\u003e","brand":"Lumatek","offers":[{"title":"Default Title","offer_id":52071525187882,"sku":"LUM-LGT-BALLAST-400W","price":139.95,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0847\/1573\/3290\/files\/400wballast.webp?v=1783914333","url":"https:\/\/www.thegrowguys.com.au\/products\/lumatek-400w-digital-ballast","provider":"The Grow Guys","version":"1.0","type":"link"}