How Theatrical Lamps Are Identified
All theatrical lamps, also known as Stage & Studio lamps, have a unique code to help identify them for replacement. The most common is a 3-letter ANSI (American National Standards Institute) code such as BTL, FEL, or HPL; however, the lamp could also be identified by a 4 or 5-digit number.
If you know the 3-letter code or the 4 or 5-digit number, those are unique to that lamp type, and that is typically all the information you need to order replacement theatrical lamps.
HPL Lamps for ETC Source 4 Fixtures
If you have any incandescent fixtures manufactured by ETC (Electronic Theatre Controls), the lamp type is HPL, although there are a wide variety of HPL lamps that will fit in your fixture. The letters HPL are followed by Wattage and voltage, and sometimes a letter or two.
For example: HPL575/115 is a 575 Watt lamp, which is designed to operate optimally at 115 volts.
Extended Life vs. Standard Life
If the voltage is followed by an “X” or “LL,” that stands for eXtended or Long Life. Please note that eXtended or Long Life lamps do last approximately 5 times longer than standard life lamps (300 hours), albeit at a 25% reduction of lumen output. Most professional theatres prefer the HPL575/115, while many schools and houses of worship go for the HPL575/115X to achieve extended lamp life, even with the sacrifice in output.
Understanding Voltage
Voltage is an important consideration when replacing lamps. 115-volt lamps are designed to be used on a dimmer system, which has some inefficiencies that prevent full input voltage from reaching the lamps. By utilizing 115-volt lamps on a dimmer system, you can achieve full output from your lamp and fixture. If you are plugging a fixture straight into the wall receptacle, go for the 120-volt version to achieve the rated life.
HPLs are also available in 77 volts to be utilized with ETC Dimmer Doubling.
Wattage: 375, 575, or 750?
HPLs are available in 375, 575, and 750 Watts. 750-Watt HPLs work great in ETC PARs, ParNels, Multi PARs, and ETC Fresnels; however, we do not recommend them for ERS (Elliptical Reflector Spotlights). To achieve the higher 750-Watt lamp, the manufacturer lengthened the filament and in doing so, exceeded the area from which filament output could be efficiently captured by the elliptical reflector. In side-by-side comparisons, most humans cannot distinguish between a 575 and 750 in a Source 4 ERS.
G9 Base (Bi-Pin) Lamps
G9 Base, also known as Bi-Pin, is the most common base for most non-ETC Elliptical Reflector Spotlights. These are available in a variety of Wattages and voltages. It is important to check your fixture for the maximum acceptable Wattage when replacing the lamp.
FEL Replacements
Many fixtures will accommodate the 1000-Watt FEL; however, the elliptical reflector cannot capture all the output so much is lost inside the fixture and goes to waste as heat. The single-coil filament FLK (575 Watts), originally sold as the HX-600, is a great replacement for the FEL, EHG, and EHD. There is also a long-life version, FLK/LL, originally sold as the HX-601.
With a slightly different filament design (four smaller coils clustered together instead of one large coil), the GLC (575 Watt), originally HX-604, and LL version GLA, originally HX-605, are also great replacements and are the specified lamp for many newer ERS fixtures.
Need Replacement Lamps?
We stock HPL, G9, and other common theatrical lamps for same-day shipping. Call (816) 221-6966 or order online. If you’re unsure which lamp fits your fixture, call us with the fixture model and we’ll identify the correct lamp.