Product Overview
GE Constant Color Plus 70W CMH G12 Lamp - 3000K T6 Ceramic Metal Halide
The GE Constant Color Plus 70W Ceramic Metal Halide (CMH) is a premium T6 tubular lamp featuring a G12 ceramic bi-pin base and advanced Constant Color Plus technology. Delivering 6,200 lumens of warm 3000K white light with superior 90+ CRI color rendering, this lamp is ideal for high-end retail displays, museum lighting, and commercial applications. With a 15,000-hour rated life, UV control, and universal burn position, it provides consistent color stability and exceptional performance.
Technical Specifications - GE Constant Color Plus 70W
Electrical
| Wattage | 70 Watts |
|---|---|
| Lamp Operating Voltage | 90 Volts |
| Base Type | G12 Ceramic Bi-Pin (12mm spacing) |
| ANSI Ballast Code | M139 / C139 (Pulse Start) |
| Certifications | CE, RoHS |
| Origin | Hungary |
Photometric Performance
| Color Temperature | 3000K (Warm White) |
|---|---|
| Color Rendering Index (CRI) | 90+ (Excellent - Constant Color Plus) |
| Initial Lumens | 6,200 lm |
| Efficacy | 88.6 Lumens per Watt |
| Rated Life (L70) | 15,000 Hours |
| Lumen Maintenance | 90% at 40% of rated life |
Physical & Thermal
| Bulb Designation | T6 Clear (Tubular 6/8") |
|---|---|
| Maximum Overall Length (MOL) | 3.56 inches (90.4mm) |
| Bulb Diameter | 0.86 inches (21.8mm) - T6 |
| Light Center Length (LCL) | 30mm ± 2mm |
| Burning Position | Universal (Any orientation) |
| Max Base Temperature | 250°C (482°F) |
| Max Bulb Temperature | 400°C (752°F) |
Compatible Ballast Systems - ANSI M139/C139
⚠️ ANSI Code Correction
The specification lists M85/M98/M139, but 70W CMH lamps require ANSI M139 or C139 ballasts.
- M85: Typically for 35W CMH (do not use with this 70W lamp)
- M98: Typically for 39W CMH (do not use with this 70W lamp)
- M139: Correct for 70W CMH (this lamp)
- C139: Ceramic Metal Halide variant of M139
Using incorrect ballast wattage will cause lamp failure and void warranty.
Recommended Ballasts:
- GE GEMH70 series (M139/C139 rated)
- Philips Advance Xitanium 70W CMH (M139)
- Osram PT-FIT 70 (M139 compatible)
- Sylvania Quicktronic 70W CMH (M139)
Socket: High-temperature G12 ceramic bi-pin rated for 250°C+.
Constant Color Plus Technology
GE's Constant Color Plus represents the premium tier of CMH technology:
- Enhanced CRI: 90+ Color Rendering Index (vs. 81-82 on standard CMH)
- Superior Color Stability: Maintains 3000K ±100K throughout 15,000-hour life
- Improved Lumen Maintenance: 90% output at 40% of rated life
- UV Control: Integrated ultraviolet filtration protects merchandise and artwork
- Compact Arc Tube: T6 design provides precise optical control
Best for: High-end retail, jewelry stores, museums, and critical color applications where 90+ CRI is essential.
Constant Color Plus vs Standard CMH
| Feature | GE Constant Color Plus (This Lamp) | GE Standard CMH | Standard Metal Halide |
|---|---|---|---|
| CRI | 90+ (Excellent) | 81-82 (Very Good) | 65 (Fair) |
| Color Stability | 3000K ±100K | 3000K ±200K | Shifts to green |
| Lumen Maintenance | 90% at 40% life | 80% at 40% life | 60% at 40% life |
| Best Application | Color-critical retail/museums | General commercial | Industrial only |
| Price Premium | ~15-20% higher | Standard | Budget option |
Professional Applications
High-End Retail
- Fine jewelry and watch displays (90+ CRI shows true colors)
- Designer apparel boutiques
- Cosmetic and skincare counters
- Luxury goods showcase lighting
- Art gallery retail spaces
Museums & Galleries
- Artifact and artwork illumination (UV control protects pieces)
- Rare book and manuscript display
- Sculpture accent lighting
- Temporary exhibition lighting
- Conservation-grade lighting systems
Commercial & Hospitality
- Five-star hotel lobbies and common areas
- High-end restaurant ambiance
- Corporate reception art programs
- Architectural feature lighting
- Recessed downlights (4-6 inch)
Compatible Replacements - G12 Base 70W
This GE Constant Color Plus 70W (G12, 3000K, M139) cross-references to:
| Brand | Part Number | CRI | Notes |
|---|---|---|---|
| Philips MasterColor | CDM-T 70W/830 G12 | 81 | Standard grade |
| Philips MasterColor Elite | CDM-T Elite 70W/930 G12 | 92 | Comparable to Constant Color Plus |
| Osram Powerstar | HCI-T 70W/830 WDL G12 | 81 | Warm Deluxe |
| Sylvania Metalarc | MC70T6/U/G12/830 | 81 | Standard grade |
| GE (Standard) | CMH70T/UVC/830/G12 | 81 | Non-"Plus" version |
The "Constant Color Plus" designation indicates this GE lamp competes with Philips MasterColor Elite (90+ CRI tier).
Safety Information & Compliance
⚠️ UV Radiation Warning
This lamp emits shortwave UV radiation. Despite UV Control technology, it requires:
- Enclosed fixtures meeting UL standards
- Adequate shielding in occupied spaces
- Immediate replacement if outer envelope damaged
- No use in open fixtures or residential living areas
? Thermal Management
- Max base temperature: 250°C (ceramic socket required)
- Max bulb temperature: 400°C
- Allow 15-minute cool-down before handling
- High pressure operation - handle carefully
- Universal burn position approved
? Compliance Standards
- CE: European Conformity
- RoHS: Restriction of Hazardous Substances
- ANSI: M139/C139 compliant
- UPC: 043168200165
- Origin: Hungary (EU manufacturing)
Frequently Asked Questions
What is the difference between Constant Color and Constant Color Plus?
Constant Color Plus is GE's premium CMH line featuring 90+ CRI (Color Rendering Index) compared to 81-82 CRI on standard Constant Color lamps. Plus versions also offer better lumen maintenance (90% vs 80% at mid-life) and tighter color consistency (±100K vs ±200K). Choose Plus for high-end retail, museums, and applications where color accuracy directly impacts sales or preservation.
What ANSI ballast should I use for this 70W lamp?
Use only ANSI M139 or C139 rated ballasts designed for 70W Ceramic Metal Halide. The specification sheet mentions M85/M98/M139, but this appears to be an error—M85 is for 35W, M98 is for 39W, and M139 is correct for 70W. Using a lower wattage ballast will cause failure; using higher wattage will damage the lamp. Verify your ballast is specifically rated 70W M139/C139.
Can I use this in a G8.5 socket?
No. This lamp requires a G12 socket (12mm pin spacing). G8.5 sockets have 8.5mm spacing and are physically smaller. Attempting to force this T6 lamp into a G8.5 socket will damage the socket and lamp. Verify your fixture has G12 (12mm) ceramic bi-pin sockets rated for 250°C before ordering.
Is the T6 bulb larger than T4.5?
Yes. T6 indicates 6/8 inch diameter (0.75" or 19mm, though this lamp specifies 0.86" which is slightly larger due to the outer jacket). T4.5 is smaller at 4.5/8 inch. This GE Constant Color Plus uses the T6 designation but with actual diameter of 0.86" (21.8mm). It's compatible with standard G12 fixtures designed for T6 tubular CMH lamps. The larger diameter provides slightly better lumen output than T4.5 equivalents.
Why is 90 CRI important for retail lighting?
90+ CRI (Color Rendering Index) means the light source shows colors nearly as accurately as natural sunlight (100 CRI). For retail, this is crucial because: (1) Customers see true product colors, reducing returns; (2) Red merchandise (R9 value) appears vibrant rather than dull; (3) Skin tones look natural, encouraging try-ons; (4) Jewelry and metallics sparkle accurately. Stores using 90+ CRI typically report higher conversion rates compared to those using 80 CRI lighting.
