Technical Support Document 036 - 5/97

THE MANUAL CONTROL TEST

This test allows the user to run various systems in the Starlite individually, and without computer intervention. It will test Filter Blade and Shutter movement, Color Sensor response, as well as Lamp Voltage Regulation and Control.

To enter this test, go into the Diagnostics menu, and select the first item, MANUAL CONTROL TEST. (Press MENU, <8>, ENTER, ENTER.) Key responses in this test are very slow, so press any keys used for testing very slowly.

While in the test, the screen will appear as shown below. The various portions are explained below, followed by the actual test routines.

1 Base Filtration Values. These are the Cyan, Magenta, and Yellow filtration values as read directly from the color sensor. These are raw values, and have no offsets added to them.

2 Display Filtration Values. These are the D,C,M,Y values as shown on the main screen during normal operation. They are calculated using all offsets in effect, including the Master Color Balance Offsets, Emulsion Offsets, etc.

3 Color Sensor Voltages. These are the voltages, in millivolts, that the color sensor is actually putting out. The Starlite uses a logarithmic light sensor, so these voltages will not

reach zero when the lamps are turned off.

4 Lamp RMS Voltage. This is the amount of AC mains voltage being sent to the lamps. This voltage will range between about 7 volts up to the rated voltage of the lamps in the Starlite.

I. FILTER BLADE MOVEMENT

In the test screen, the number-pad keys are used to actually move the filters. The keys are operated like up/down arrows, not as number entry keys. The chart below shows the usage of keys to move the filters and shutter.

For Example, press and hold the <3> to pull the Cyan filter all the way out of the light path.

To check filter movement:

1. Open the Starlite's door and tape the safety interlock switches so that the head may be run with the door open. Leave the mixing chamber in place while the head goes through it's power-up procedure.
2. Turn the power on in the normal manner.
3. When the Colorhead reaches the normal operations screen, access the Diagnostics Menu for the MANUAL CONTROL TEST, as described in the beginning of this document.
4. Once in the test screen, remove the mixing chamber to give a better view of the filter blades.
5. Move the Yellow filter blade all the way out of the light path by pressing and holding the <7> key. While doing so, look at the blade itself to see if the movement stops before reaching full open. Also listen for any excessive noise while the filter is moving. The movement should be smooth and even, with no binding or hesitation.
6. Repeat step #5 for the Magenta then the Cyan Blade. Use the <6> and <3> keys, respectively.
7. Next, try the shutter. Pay extra attention to the shutter's movement, since most failures associated with blade movement are associated with the shutter. ( It does the most work in normal operation.)
8. If the movement of all three blades and the shutter, out of the light path, is clear, proceed to close all the filters, in turn.
9. Start by closing the shutter, then proceed with Cyan, Magenta, then Yellow. This will allow a clear view of each blade as it closes.

This completes the visual test of the filter blade movement. If everything checks out, please proceed to the next section.

II. COLOR SENSOR RESPONSE

The test for the color sensor is essentially the same as that for the filter movement. However, it is done with the mixing box in place. Since this test relies on the fact that the filter movement is correct, the previous test should always be done prior to this one. The theory of this test is that each filter will change the amount of light for it's particular color by about 220cc's, from fully-opened to fully-closed. The color sensor should be able to read this range of light output for each channel. Sensor stability will also be examined. During this test, please refer to the screen layout and number-pad function chart at the beginning of this document, if needed.

To test sensor response:.

1. Install the mixing chamber into the Starlite enclosure in the normal manner.
2. Check that there is tape over the safety interlock switches, and turn the power on.
3. After the Starlite has reached the main operating screen, access the Diagnostics menu and activate the MANUAL CONTROL TEST function.
4. In this test screen, move all filters all the way out of the light path. The shutter must also be open.
5. Turn the Starlite's lamps on by pressing the LAMP key. Key response while in this test mode can be sluggish, so press keys slowly.
6. The upper, left set of numbers on the screen will start to indicate the filtration of light being read by the color sensor.
7. Once these numbers stabilize, take a note of each of the three values. The actual values are not important, but all should usually be below 100.
8. Watch the numbers for signs of excessive movement.
   > The numbers should maintain their values within about 2 or 3 points.
   > If there is a stability problem with the Starlite's color sensor, the numbers will fluctuate by 5 points or more.
   > Fluctuations less than 5 points, yet more than two, usually indicate a lamp voltage stability problem. (This will be tested in the next section.)
9. If the numbers appear stable, continue the test by closing each filter, in turn, with the lamp still on. As each filter moves, it's corresponding number should climb to a positive value that is at least 190 cc's more than the value noted in step #7. They are usually 220-230 point different. Also check that each filter affects only it's particular color by a large amount.
10. After all three filters are all the way in the light path, watch them once again for stability. They should not fluctuate any more than they did in step #8.

If all of these things check out all right, the Starlite's color sensor is functioning properly.

III. LAMP VOLTAGE REGULATION AND CONTROL

The Starlite's lamp voltage regulation and control is controlled by the computer. The maximum and minimum lamp voltages are set when the Starlite is turned on.

The computer allows the user to monitor and test the performance of the lamp control circuitry from the Manual Control Test screen.

This test is a simple matter of running the lamps dimmer and brighter, comparing the light output with the voltage display.

The voltage going to the lamps during the Manual Control Test is shown in the lower, right-hand corner of the keypad display. The voltage is controlled using the right-hand set of arrow keys on the keypad. These are the set of arrow keys directly under the Enter and Cancel keys.

To check lamp voltage control.

1. In the Manual Control Test screen, turn the lamps on by pressing the LAMP key.
2. The indicated voltage on the lamps should read about 73 volts on 110-volt units, or 107 volts on 220-volt units. (These voltages are for a "Maximum Lamp Power" setting of 90%. Please see the Starlite user's manual for more information on this "Preferences" setting.)
3. Watch the lamp voltage number for any signs of instability. This number should not fluctuate more than +/-1 volt.
4. Press and hold the down-arrow under the Cancel key on the keypad. The lamps should visibly get dimmer, in steps, and the indicated voltage should decrease as well. Pay attention to this behavior. the lamps brightness should decrease, while the voltage readout also goes down. Any behavior to the contrary would indicate a problem.
5. After a while, the lamp voltage will reach it's lowest value. For 110-volt heads, this will be about 7.5 volts. For 220-volt units, it will be about 11 volts. If it is unable to reach a value close to those stated here, bottoming-out at a considerably higher voltage, there may be a problem with either the system board, or a failed power-on calibration routine that set an incorrect low-voltage. This lowest voltage should also match the voltage displayed when the lamps are turned off.

If the voltage is easily controllable and stable, the lamp circuitry is functioning properly.

At the completion of this last test, we have now checked all of aspects of the Starlite's light control system for both Density and Color.