Antares Analytical Technical Bulletin for November 2001
 
Subject: No spark at the source or sample stand.
              Note: This is not the same condition as a spark in the source but not in the sample stand.
 
Relevant Models: 
 
Relevant Matrix: Not Applicable
 
Most Probable Cause:  No "Source On" signal getting to the KH / HR source: The "Source On" signal is a safety interlock built into your Baird spectrometer so the source will not fire while the sample stand covers are open. A bad interlock switch or other spectrometer problem can cause this signal to not reach the KH or HR source.
 
The basic "source on" interlock circuitry is a 24 VDC or a 115 VAC signal (depending on the Spectrometer Interface Board ... see notes below) sent from the spectrometer into the stand safety interlock switches amd then down into the spectrometer interface board. A relay, or series of relays, then closes allowing this "source on" signal to reach the source and allowing the source to fire.
 
Note: Before troubleshooting the source on signal, other basic things should be checked first as listed below:
Troubleshooting Guide: This has ben listed in the most logical order to find the problem in the least possible time.
 
Step 1 Find if the problem is in the KH / HR source or in the spectrometer
 
DV & FSQ with HR400:
  1. Disconnect the power cable from the rear of the HR400 and remove the top cover. In the middle of the source will be the Source Fiber-optic (F/O) Interface Board which will have from 5 to 8 F/O cables going into it.
  2. Carefully pull out the J1 F/O cable. These cables numbers are all marked on the cables and on the interface board. J1 is the first cable from the REAR of the source F/O interface board.
  3. Start a burn in Routine or Test Analysis and watch the end of the CABLE. During preburn and expose a red light should show in the cable itself. If you see this light it tells you the spectrometer is supplying the "source on" signal and the problem is probably in the HR400 source. Contact Antares Analytical for advice then.
  4. If no red light is seen, the problem is probably in the spectrometer and go to the next step in this bulletin.
DV & FSQ with KH3-5
  1. At the rear of the KH is a large green connector plugged into the back of the KH at the upper rear right corner. This is the KH Source Control Cable. Take out the 110 VAC power cable and disconnect this green connector.
  2. Using a multi-meter set for a minimum of 110 VAC put the leads into the FEMALE pins A and B of the green connector. Voltage during preburn and expose will be 110 VAC and polarity is not important.
  3. Begin a burn in Routine or Test mode and watch the multi-meter for a 110 VAC voltage reading. If you see the 110 VAC reading then the spectrometer is supplying the correct signal and the problem is probably in the KH. Contact Antares Analytical for advice.
  4. If no 110 VAC is shown, check the following:
  5. On a UFO board equipped spectrometer check to see if K4 on the UFO board is energizing. If not replace the relay and retest
  6. On the older style Spectrometer Interface Board, check to see if K14 is energizing. If not replace the relay and retest.
Step 2  This will be for the FSQ or DV with an HR400 only. This will show a quick check of the Universal Interface Board and MC20 check.
  1. On the FSQ the Universal Fiber Optic (UFO) Interface Board is  located under the top cover of the spectrometer. On the DV series it is located at the back of the spectrometer behind the source.
  2. The UFO board will have 2 different sets of F/O cables with different colors. The set going to the source sends signals ONLY from the UFO to the source and may be light grey in color. The darker blue cables send signals from the MC20 to the UFO board.
  3. The "source on" signal comes into the UFO board on the J1 F/O cable from the MC20. Pull out this J1 F/O cable, start a burn, and watch for the red light coming from the MC20 during preburn & expose. If there is no light coming into the UFO from the MC20, the problem is probably farther up in the spectrometer so fo to step 3.
  4. If light comes into the UFO but not out to the source, he problem is most likely in the UFO board and it most likely a failed relay. Replace relays K1 and K2 and this will probably solve your problem.
Step 3 Determine if the problem is in the stand interlocks or somewhere else in the spectrometer
 
FSQ with KH or HR Source:
  1. Under and behind the sample stand, above the Hg alignment knob, will be a small white pull-apart type connector with 2 wires on each side. This may be a little difficult to find but it is up there.
  2. When you find the connector, pull the connector apart and work with the stand side of the connector. This will have to 2 wires going up into the sample stand. The other side will have 2 wires going down into the spectrometer.
  3. Be sure both sample stand doors are closed. Using a multi-meter set to the ohm scale place the leads on the pins in the connector. If the sample stand switches are good you will see no resistance, assuming bith stand covers are closed. Test by opening and closing the upper and lower sample stand covers. When either, or both, covers are opened, the meter should show infinite (total) resistance.
  4. If infinite ohms are measured whether the stand covers are opened or closed then the problem is probably a bad interlock switch. The top and bottom switch should be tested alone to find and replace the bad switch.
  5. If you see zero ohms with covers closed and infinite ohms with covers open, the problem is somewhere else in the spectrometer.
  6. FSQ with HR400: If the stand interlock switches check good, test the side of the connector coming from the spectrometer bringing the stand interlock cover voltage to the interlock switched
  7. Using a multi-meter set to a minimum 50 volts DC, connect the meter leads to the side of the white connector coming from the spectrometer, start a burn in the Routine or Test mode and watch for a 24VDC signal during preburn and expose. 
  8. FSQ  with KH5: If the stand interlock switches check test the side of the connector coming from the spectrometer. Using a multi-meter set to a minimum 250 volts AC, connect the meter leads to the side of the white connector coming from the spectrometer, start a burn in the Routine or Test mode and watch for a 110 VAC signal during preburn and expose. 
 
DV series with KH or HR
  1. The connector is located inside the spectrometer behind the sample stands so the top cover of the DV will need to be removed to access this connector.
  2. Since the DV can take 2 sample stands the side of the connector going up to the interlock switches will be wired into 2 other same type connectors so they will form a Y going to the 2 sample stands. When there is only 1 stand, the connector normally used for the 2nd stand will be jumped at the 2nd connector.
  3. All measurements made should be made at the 1 connector which connects with the female side going to the spectrometer.
  4. All measurements should then be made using the steps mentioned above.
  5. KH5 will be 110 VAC ... Interface board is not important
  6. HR400 will be 24 VDC .... Interface board is not important.
If you do not find the problem using the abive steps please contact Antares Analytical and we will be happy to assist you further.
 
This monthly Technical Service Bulletin has been sent to you by the Technical Service Staff of Antares Analytical. Our purpose for sending this is to help the Baird spectrometer user get the lowest cost, best use of your Baird spectrometer. If you  have any comments, suggestions for future Technical Bulletins, questions about the month's topics or questions / problems about your Baird spectrometer please contact us at:
 
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