Metal-halide (long-arc) lamp for PCB, screen-printing and plate exposure units, 180 mm, gallium-doped (Ga). Also listed as Theimer TR 1700, Ushio 500-0071 and 2 more part numbers.
Send the part number, a photo of the old lamp and your exposure unit model. We check length, base, doping and power and quote within 24 hours.
The same lamp — same overall length and spectrum — appears under all of these numbers in published replacement-lamp catalogues. Brand names identify the original part only.
| Brand | Part number(s) |
|---|---|
| NuArc | HT 121 GA |
| Theimer | TR 1700 · TH 1700 |
| Ushio | 500-0071 |
| BLV | MHL 121 HT |
Shown for navigation only — a lamp only fits if length, base and doping all match your unit.
In published replacement-lamp catalogues the same lamp (same overall length and spectrum) is listed under 5 part numbers: NuArc HT 121 GA, Theimer TR 1700, Ushio 500-0071, BLV MHL 121 HT, Theimer TH 1700. Confirm the length, base and doping of the lamp in your unit before ordering.
Yes — send the part number on your old lamp, a photo of its label and ends, and your exposure unit model. We check overall length, base, doping and power against the original before we quote, and quote within 24 hours.
The metal added to the mercury fill (iron, gallium or none) sets which UV and violet wavelengths the lamp emits. Your dry film, solder mask, screen emulsion or printing plate is sensitised to particular wavelengths, so the replacement should carry the same doping as the original.
Specifications and cross-references compiled from published lamp-maker data (Ushio, Alpha-Cure) and a US replacement-lamp distributor's catalogue. Where sources differ the values are shown side by side. Data is given for identification only — verify against your unit's manual. Lamps supplied by Kilowatt Lamps are compatible replacements and are not made by or affiliated with the brands named.