OSRAM SON T PLUS 400w

Description

OSRAM SON-T PLUS 400W is the professional-grade high-pressure sodium lamp from one of Europe’s most respected lighting manufacturers, delivering consistent, high-output illumination for grow rooms where a full 600W system would be oversized. We have been recommending OSRAM SON-T lamps to UK growers since 2017 because Osram’s manufacturing precision and batch-to-batch lumen consistency set a standard that generic or budget alternatives consistently fail to match — and in a smaller growing space, consistent lamp quality matters just as much as in a larger one.

Why 400W HPS Still Has Its Place in Modern Growing

In the age of high-power LED, the 400W HPS maintains a clear niche: it is the ideal single-light solution for grow tents from 80x80cm to 1.0×1.0m, delivering a proven, well-understood spectrum and light distribution pattern that generations of growers have dialled in for excellent flowering results. At 400W the lamp produces approximately 55,000 lumens initial output — more than adequate for a compact canopy — while keeping heat output and electricity consumption manageable in a small tent without supplemental cooling. The OSRAM SON-T Plus specification ensures consistent output throughout the lamp’s 10,000-hour rated life, with better than 85% lumen maintenance at end of life versus cheaper brands that can drop to 70%.

Setup and Replacement Schedule

Use the OSRAM SON-T Plus 400W in a compatible 400W reflector and magnetic or digital ballast — Adjust-A-Wings and Lumii Black reflectors are both fully compatible. Replace annually or at 10,000 hours, whichever comes first. Handle the lamp with clean cotton gloves to prevent skin oils on the glass causing stress fractures during thermal cycling. Allow the lamp to cool for a minimum of 15 minutes before restarting after an interruption to the power supply, to prevent premature arc tube failure from hot re-strike.

Pair the OSRAM SON-T Plus 400W with a Lumatek 400W digital ballast and an Adjust-A-Wings Enforcer reflector for a complete, proven HPS lighting package for small to medium growing spaces.