Kappa(X8)APEX

• Safety instructions
• Pre-installation requirements
• Maintenance and repairs
• Troubleshooting

Safety instructions

• X-ray
• Beryllium

Safety rules as addition to the User Manual:

• The equipment must be serviced and maintained by qualified personnel who are trained with the hazards of and precaution against X-ray exposure.
• The equipment contains safety circuits which should not be overridden, other than supplied: the service key, door lock connector and beamstop override vane. These overrides may only be used for service and maintenance.
• When using the beamstop override vane (only for alignment) the system must not be left unattended. Theta always at 0° and a low kV/mA setting as described in the alignment instructions.
• Safety circuits must be tested by service personnel or the safety officer at least every 12 months, as described in Maintenance
• The collimator must always be installed.

The detector and X-ray tube contains windows of beryllium. In normal use these area's cannot be reached, but during maintenance, care must be taken not to touch these windows. When by accident the beryllium is touched, wash with soap and water.

Fumes and dust from beryllium metal can be hazardous if inhaled. During use, corrosion of the beryllium window may occur, but it should not be cut, machined or otherwise removed. Tube and detector disposal must comply with the national and local regulations governing beryllium.
 

Maintenance

• Regular maintenance
• Cleaning
• Tools
• Server program
• Safety test
• X-ray optics alignment
• Effic: intensity of the primary beam
• Repair small shutter
• Remove bootstart of BIS

• See Lytron cooler manual

For cleaning use a damp cloth, moistened with water or isopropyl alcohol. No cleaning agent may enter the goniometer.

Tools

• Absorber: Zirconium (for Mo) or Nickel (for Cu) filter, placed on the collimator to attenuate the intensity of the primary beam to a measurable and save level. It is only allowed to used with low kV/mA settings. Specification:
• Mo: 7 foils of 0.108 mm Zr, attenuation approx. 2400x
• Cu: 9 foils of 0.02 mm Ni, attenuation approx. 1900x
• Half-beam absorber: a 2 mm bar, placed in the crystal head.
• Safety overrides, only allowed to be used during technical maintenance (see safety rules).
• Service switch which overrides the radiation enclosure safety. This state is signalled by the flashing Service  lamp.
• Door lock connector which overrides the door lock safety.
• Beamstop override vane. There are no extra warnings.
• Test crystal: Ylid

Server program

If the server program window is not visible it can be restored by editing a new line with SHOWWINDOW in C:\program files\brukeraxs\bcp and pis\KCCD.SET
 

Safety test

This test it limited to some safeties in the goniometer without an internal failure check:

Shutter safety

• Switch off the X-ray high voltage
• Open the shutter in Server with Acquisition, Toggle shutter.
• Check if the shutter not open after activating the next unsafe conditions. The shutter must remain closed after reestablishment of the safety (except the shutter lamps):
• Collimator removed.
• Beamstop removed.

X-ray optics alignment

Safety precautions

1. Don't let other persons come in the neighbourhood of the system.
2. Don't leave the system unattended, before reestablishment of the safety.
3. Don't come in the primary beam, although for security reasons it is attenuated to a weak and safe intensity.

Measurement set-up

1. Service key on and door lock connector on the service panel.
2. The main shutter can be opened by pressing the red shutter button on the service panel for 5 seconds.
3. Place a #353 collimator
4. Place the absorber on the collimator (take care: Mo and Cu use different absorbers).
5. Remove the beamstop and place the red vane (safety switch override).
6. X-ray generator:
• Mo: 30 kV, 10 mA
• Cu: 20 kV, 10 mA
7. For measurements use in BCP: Tools, Halfbeam

Adjustment

1. Adjust Tube 2Theta to 0°.
2. Dismount the monochromator and mount the X-ray port (two Allen screws {2.5 mm} at the bottom, which can be reached by two holes {not the middle one} under the black monochromator holder). During replacement the power of the X-ray generator must be off.
3. Adjust tube 2Theta = 0° and take-off = 3.0° (for fine focus 0.4 x 8 mm).
4. Adjust on approx. maximum intensity with tube vertical and tube horizontal adjustment (measurement Continuous)..
5. Mount the half-beam absorber (3 mm bar) on a goniometer head. Align it with the microscope with /  and Phi 90° rotated: the edge of the bar must be in the centre (it must absorb half of the beam).
6. Align horizontal and vertical:
• Start a measurement (horizontal or vertical). Two measurements are executed with Phi 180° rotated.
• Both measurements must be equal within 5%. If not : adjust with tube horizontal or vertical adjustment to the proposed "new" value (with measurement Continuous) and measure again.
• Lock the tube vertical adjustment.
7. Test the alignment of the half-beam absorber :
• Remove the half-beam absorber and measure Open.
• Place the half-beam absorber and measure Vane. The error should be not more than 25%. If it is : adjust to the advised new value and measure again. When the alignment was bad, check the previous tube alignment again.
8. Remove the half-beam absorber and X-ray port. Switch off the power of the X-ray generator during replacement.
9. Mount the monochromator and switch on the power of the X-ray generator.
10. Adjust Tube 2Theta (Mo: 12.2°, Cu: 26.6°) and the Monochromator Theta on the anode target material used.
11. Adjust the intensity on maximum. First with monochromator 2Theta, then tube 2Theta and monochromator height.
12. Lock the monochromator height.
13. Measure the open intensity.
14. Mount the half-beam absorber and position horizontal with "Vertical" (don't use the result of this measurement). Measure continuously and adjust with monochromator theta till the intensity is half the previous measured open intensity ±10% (a first coarse alignment).
15. As before, adjust the intensity within 5%:
• Vertical : with monochromator theta (with measurement vertical)
• Horizontal : with tube horizontal (with measurement horizontal).
16. Lock the monochromator Theta.
17. Set the X-ray generator to 10 mA and measure the open intensity (measurement Open) without the half-beam absorber. This is the Effic value.

Adjustment points

EFFIC: intensity of the primary beam

The Effic measurement is a relative measurement of the intensity of the primary beam, which measures the total efficiency of the X-ray: tube, optics and detector gain. When the value is too low it is mostly caused by the tube (degradation) or the X-ray alignment. The measurement is done during installation of the system and later measurements can be compared with this value. Take into account that because of tolerance in collimator and absorber (material thickness) the values cannot be accurately compared with other systems.

Measurement:

• 353 collimator with Mo or Cu attenuator
• DX = 6 cm
• Mo: 30 kV, 10 mA
• Cu: 20 kV, 10 mA
• Replace the beam stop by the red vane
• Measure the intensity in BCP: Tools, half beam: no tool, 10s (shows cps, ADU/s, beam image)

Bootstart BIS remove

• Check with ctrl-alt-delete. After power on, no "InstrumentServi" should be active. If there is, remove bootstart with:
• Start/Programs/Startup/BIS. (advise: delete)  or:
• Start-settings-controlpanel, Administrative Tools, double-click Services, choose Bruker Instrument Service, Action-properties: automatic or disabled. (advise: disable)

Troubleshooting

When consulting Service always run D8tools, make a status file (.sts) and send it to the service center

• General:
• In APEX(2): Instrument, Status and check for warnings
• Start D8tools
• Check on error messages
• Contacting service
• Make in D8tool a .sts status file (File, Save) and include it in your email.
• Mention in the subject: SCD and the System Serial number
• Resetting HV errors
• Start-up, PC and communication  problems
• Shutter does not open
• HV goes off
• Collision and maximum angle switch
• X-ray intensity or images problem
• Black dust in fast shutter and monochromator
• Detector problems
• Lytron cooler

Serial number
 

A service department will often ask for the system serial number. All parts has its own serial  number, but also the whole system has a serial number. It is a number 1-9999 (from Madison factory) or a 4.... number (From Delft). It can be found on one of the three places: C) The right side post just below the leds. (Most probably) B) The right top of the rack underneath the enclosure. A) The top left brace behind the glass.

Using D8tools

D8tools is the program to check for errors in the X-ray dafety en shutter circuit. Start:

• In BIS give the manual command: [manual/mode=1]
• Start D8tools, On line status, bar-button: refresh on
• File, Save as. Send this .sts file to the service center

Resetting HV errors

• Start D8tools
• Go in the left directory to: "x-ray generator / x-ray software safety circuit capture register"
• Select from the menu: "utilities / x-ray / reset x-ray software safety circuit capture register"  (default password = "password").
• Wait some time.
• Switch on the HV with the button on the side panel.

Start-up, PC and communication problems

• PC-server program remains in: present operation = Goninit
• Kappa does not move and Omega is slowly running to its maximum position: check the dummy plug on the goniometer connector 'Limit switch'. Before replacing first switch off/on the Interface.
• Add at the top of the start-up file C:\Program Files\BrukerAXS\BCP and BIS\KCCD.SET the line:  SKIP_ZERO.  (take care to remove this line after testing !) After start-up:
• Present operation = none (system has started) : It is a problem in the goniometer. Inform the service department
• Present operation = Goninit (system does not start) : It is a problem in the Interface.
• Starting BIS gives no response: Ctrl-Alt-del, Task Manager, end all InstrumentServi processes
• PC error messages
• "Failed to open serial port for goniometer controller, in use or not present", Timeout ..., "Failed to initialize communications with the goniometer controller. This will happens when BIS was already started before nd has occupied the comport.
• Check with ctrl-alt-delete. After power on, no "InstrumentServi" should be active. If there is, remove it.
• This can happen went BIS is started during PC-boot. We advise to disable this bootstart

Shutter does not open

• The shutter is normally closed when
• The collimator is not in the right position.
• The monochromator or X-ray port is not in the right position.
• The beamstop is not mounted.
• The shutter open lamps are defect.
• The radiation enclosure is not closed.

HV goes off

• Start D8tools and check for red alarms during switching on the HV.
• Reset errors

Collision and maximum angle switch

The anti-collision software prevents the goniometer from colliding with the collimator holders or the axis to run past their limits. When a collision takes place because of unexpected circumstances, like a technical error, it is sometimes possible to return:

1. On the Server computer a menu appears.
2. Choose the axis and direction to run out of collision.
3. Press the overrule button at the back of the goniometer. The axis now positions a small step.
4. If not enough: repeat. As soon as the collision switch is released, the goniometer starts to relocate the zero position.

X-ray intensity or images problem

• No X-ray (but no error messages):
• Check if there is also no X-ray with the Effic measurement.
• If the main shutter opens (audible and visible) and the led on the small shutter is on, then probably this shutter should be cleaned of replaced.
• X-ray too low:
• Check the Effic measurement and compare it with earlier measurements. With a new tube check first if Effic without monochromator is not too low (not possible in K3). The intensity with monochromator is about 60% of the intensity without monochromator.
• Mostly a low intensity is caused by the X-ray tube. When you want to be sure the error is not in the detector you can check the intensity of the primary beam with a separate detector (for instance a scintillator detector usable for 8-18 keV).
• Check the alignment of the goniometer. Perhaps the primary beam doesn't go through the centre of the goniometer. It is also possible to test it by using a small 0.4 mm steel ball on the crystal position and make an image of the primary beam (Always with absorber and low kV/mA setting)
• Remove the collimator, switch off X-ray, look into the collimator hole and check for black powder. Some fast shutters produce black dust which absorbs the X-ray. Mostly it can be blown away with compressed air. The black powder can also be on the monochromator crystal. The cause is when the plunger is too sharp, which then wears the brass. This can be solved by making the top of the plunger soft soft with a whetstone, not with a file (mostly the edge, but also no carves on the surface).
• No images
• Check in APEX2server Instrument status for warnings that the files cannot be saved. This can be caused by connection problems with the client PC.

Detector problems

• Restart: first power up the D8 and wait till it has started up. Then power on the detector.
• CCD temperature (can be checked in the image file header)
• APEX I
• The default CCD temperature is:  -43 - -44 ºC (Water cooler: +5 ºC). When it goes above -40 ºC the detector should be checked of leakage and revacuumed. This can only be done in the factory.
• APEX II
• The default CCD temperature is -60 - -64 ºC . Because of outgassing in the detector vacuum this temperature will slowly rise. When it goes above -50 ºC, also after setting the cooling liquid to -5 ºC, the detector should be revacuumed. This can only be done by a service engineer.
• If there is a problem in the image, not related to reflections,  please :

• Other valuable calibration files which service can ask you to send (in the same directory, #### is the detector number):
• ####_00512_time._dk (time must be the same time the measurements with errors were done)
• ####_0512_90s._fl

Lytron cooler

• The default setting is 0 ºC
• Cooling liquid does not reach 0 ºC (for APEX II). Check if:
• There is enough clearance (45 cm) for air flow.
• The condenser coil is obstructed with dust and/or debris
• The Glycol mix ratio is too high or too low (too much a too little glycol). This can be caused by condensation inside the cooler which slowsly in time will dilute the liquid.
• The filter strainer is clogged, not allowing the coolant to flow freely through the evaporator ( heat exchanger). Clean it
• Check or replace the cooling liquid

If you cleaned or changed the filter inside the Lytron controller be sure to reinstall its isolation. Also condensation will occur which drips on electrical connections below. So it should not look as: