怪侠一把刀
第16楼2006/11/19
After cleaning the source, I suddenly have no baseline on the chromatogram. Why?
If the problem occurred after the source was cleaned, it could be as a result of the high multiplier voltage caused by the dirty source, which could cause an excessive signal level when the Mass Spec is initially tuned or scanned after the clean source is installed.
To correct this problem, lower the Multiplier voltage to approximately 1000 volts in [MAUAL TUNE] and save this value to, “[TUNE PARAMETERS]”, in the ATUNE.U tune file and re-tune the Mass Spec. If the Mass Spec passes the tune, more than likely the MS is okay.
怪侠一把刀
第22楼2006/12/02
Please perform the following checks.
If the system cannot generate the vacuum correctly, it shuts down the diffusion pump or the turbo pump, and the fore line pump.
This can be caused by the following conditions:
On the diffusion pump MSD, the vacuum did not go below 300mTorr. On the turbo pump MSD, the turbo pump speed is reduced below 80% for seven minutes.
The typical cause in these cases is a major air leak.
The side plate (on the analyzer) did not make a tight seal. The vent valve was not closed fully. The ferrule for the column on the MSD interface was not tightened.
These problems can cause the foreline pump to not remove air from the vacuum manifold. There is a risk of damage to the analyzer and pump if air is not removed.
如果系统不能正常的抽取真空,质谱会关闭扩散泵或涡轮泵和前置泵。这个可能有以下的情况造成:
MS中扩散泵系统在低于300mTorr的时候会停止运作;而涡轮泵的速度会在7分钟之后降到80%以下。这个典型的原因是严重的空气泄漏。
侧板没有密封紧、放空阀没有完全关闭、连接MS部分的柱子垫圈没有拧紧;这些问题可能导致前置泵无法抽取真空。空气的存在也是导致分析器和泵损伤一个因素。
When turning on the power to the MSD, always press the side plate to ensure it is fully closed.
If the unit still does not start, please contact the customer service center at Agilent
怪侠一把刀
第23楼2006/12/02
这个是关于最近问得比较多得关于灯丝的问题:
1、关于灯丝的维护;2 如何延长灯丝的寿命 3 如何解决灯丝烧断故障
1.What is the procedure for Maintaining MS Filaments?
· Maintaining MS Filaments:
Like the filament in an incandescent light bulb, the ion source filaments will eventually burn out. Certain practices will reduce the chance of early failure:
§ When setting up data acquisition parameters, set the solvent delay so that the analyzer will not turn on while the solvent peak is eluting.
§ When the software prompts "Override solvent delay" at the beginning of a run always select No.
§ Higher emission current will reduce filament life.
§ If you are changing your MSD from the [Edit Parameters] screen, always select MS Off before changing any of the filament parameters.
2 How to increase filament life?
· The ion source filament emits electrons when heated by the emission current. The emitted electrons ionize the sample molecules. There are 2 filaments installed on the ion source. They eventually burn out. To extract more life out of them,
Use a proper solvent delay time in the Data Acquistion parameters so that the analyzer is off when large solvent peaks are eluting.
Higher emission current will reduce the filament life.
Operating the MSD in a poor vacuum condition, with high moisture in the vacuum manifold, or high back ground will all shorten the filament life
3.How do I troubleshoot a broken filament?
· Troubleshooting a broken filament:
There is a dramatic change in the signal when a filament breaks. A typical result is a precipitous drop in the baseline during data acquisition. Also, the Chemstation will typically exhibit the NO EMISSION CURRENT error during tuning.
All 5973A/N MSDs equipped with the EI source have 2 filaments. If one of the filaments breaks, you can use the Chemstation software to change to the alternate filament. After selecting the alternate filament, go to the Edit MS Parameters screen and proceed to the
FILAMENT SELECT BOX, (which could have either FILAMENT 1 or 2 selected) and select the alternate filament. After selecting the alternate filament, try to execute a scan using the [Scan] button at bottom of screen. If the Scan is successful (meaning no errors occur), then exit the screen. This will put you back at the top level of MANUAL TUNE. At this point select [FILE], and then save the tune values to the tune file you are using.
怪侠一把刀
第25楼2006/12/07
Please perform the following checks.
1. In the Edit MS Params of the Manual Tune screen: Click the "Scan" or "Profile" button and check whether the error message appears again.
2. Next, change the filament from the screen. Click the "Scan" or "Profile" button and check whether a peak appears.
3a. If a peak appears: Close the Edit MS Params screen and use the "File" menu to save the tune parameters. You can now perform measurement after doing an autotune.
Change the filament the next time you perform ion source cleaning.
3b. If no peak appears and an error message is output: Vent the system and check whether the two filaments are broken and that the ion source cable is connected correctly. If a filament is broken, replace both the filaments.
Check that the two cables connecting the analyzer unit to the electronics are fully inserted. Side board control cable (wide ribbon cable) Source power cable (thick cable on the near side)
Try generating a vacuum again.
If there is no improvement, please contact the 啊 customer service center.