Hardware manual

Maintenance 4
Agilent 7500 Series ICP-MS Hardware Manual 4-143
Maintaining the Penning Gauge
The Penning gauge carries a high voltage as it monitors the analyzer vacuum.
Before maintaining the Penning gauge, shut down and unplug the instrument.
You need to clean this gauge if there is a sudden fluctuation in the (AN)
vacuum meter reading of more than 5x10
-3
Pa while you are monitoring the
meter. In this block, the typical change of the meter value is more than ±10%.
Spiking signals are another indication of the need to maintain the Penning
gauge.
Locating Tools and Supplies
To replace the body tube of the Penning gauge, you need the following tools
and supplies:
• Safety glasses and protective lab gloves
To properly maintain the Penning gauge, it is recommended to replace the
body. However if you clean and polish the parts inside the body tube, you also
need more tools and supplies. The tools you need to clean the Penning gauge
are not included in the tool kit. However, the tool kit, including a flat spanner
and a circlip pliers can be purchased from Agilent Technologies. The tools and
supplies you need are as follows:
• Flat spanner
• Circlip pliers (pointed nose pliers)
• Fluoro- elastomer O- ring
• Jewel driver or feeler gauge
• Polishing paper (#400 P/N: G1833- 65404)
• 2% detergent solution
• Pure water
• Laboratory tissue