Pacific Lamp: Replacement and Peak/Flat Alignment

Isolate electrically before re-lamping the luminaire. Also, please be aware that the lamp or luminaire may still be hot, so exercise the caution necessary to avoid burns.

Replacing and Centering the Lamp

  1. Remove the lamp holder module by unfastening the lamphouse locking clamp and sliding it out of the guides on the rear of the lens tube.
  2. Set the level of the metal cup holding the lamp base. The metal cup has a line around it. This level is factory set to the optimum position, and the luminaire output is then confirmed with test equipment. The optimum position has the line level with the edge of the module.

    First level the cup with the edge of the module by adjusting the three levelling screws. Then set to the correct height as detailed above.
  3. Remove the old lamp. Align the pins of the new lamp to the correct holes and push the lamp firmly home. Do not touch the quartz envelope of the lamp with your fingers - use the plastic or paper sheath supplied to insert the lamp.
  4. Carefully replace the lamp holder module and tighten the thumbscrew to lock it into position. Reconnect the luminaire to the power supply.
  5. Turn on the luminaire to approximately 30%. This makes the peak easier to see, and reduces the stress on the filament. Set the beam angle to its widest with a sharp edge.
  6. Centre the lamp in the middle of the beam if necessary, by adjusting the three levelling screws.

Optimising the Output
Peak / Flat Adjustment

The lamp position can be simply altered with a half turn in either direction of the cool planetary gear to peak or flat light output as desired.

The peak beam gives a central hot spot falling off evenly to the beam edges.  This setting is useful for normal stage lighting purposes where beams are overlapped to achieve an even cover. 

Flat adjustment provides a visually even light beam suitable for gobo projection.

Take care to move the lamp carefully as the lamp filament is burning white hot and at its most vulnerable. Don't over-tighten the knobs, finger tight pressure is all that is required.
  1. Adjust the beam to its narrow angle, with a sharp edge.
  2. 'PEAK' the output by turning the centre gear (white arrows) clockwise until you see light flare around the edge of the beam.
  3. Turn the centre gear anti-clockwise until the flare is removed and you have a clean sharp-edged beam. This is the position of maximum light output.
  4. A useful technique to check how well the lamp is centred is to push two of the shutters into the beam, and then check if any reflection off the shutters is visible in the beam. If so, adjust the screw on the side opposite to the reflection until it disappears.
  5. To set a ‘FLAT’ beam, turn the centre gear (white arrows) anti-clockwise until the distribution appears even across the beam.
All Pacific lamp sockets are spring mounted to minimise possible vibrations such as air conditioning ducting or people moving on catwalks being passed through the luminaire which can cause causing premature lamp failure.