Headamp Error List and Function Test

[describe problems with no beams, stuck beams, full scale etc.

Include errors such as no beam response in IonOS, zero problems, grounding.]

Potential problems that can be encountered with the isoprime visION Mass Spectrometer Headamp;

• Grounding problems – check Headamp case is grounding relative to flight tube (Test probe one of four corner screws which hold Headamp together)
• Lid issues – inside of removable lid is sometimes anodized and stops the electronics from grounding properly when the lid is in place – solution inside of lid filed until shiny surface is present for electronics pogo-pin.
• Sticky pogo-pins on the Headamp – causing the channels not to properly make contact with the collector pins. Sometimes removing them and swapping them with unused pogo pins can get, occasionally a new set will be needed.
• Noise on a beam – sometimes caused by a DAQ board, there are 4 boards inside the Headamp , they have the capability to be both in high and low gain, by default 2 are set high and 2 set low. If one channel is suspected of noise, swap the DAQ with a healthy channel and see if the problem persists.
• Electronic zeroing slow response – when doing electronic zeros for both high and low gains, sometime you get a slow response or slow switch over on one channel, causing incorrect electronic zeroes to be recorded. Try repeating zeroes with magnet switched off, this often fixes the switch gain switching.
• No beam response – check that the 9-pin connector is plugged into the rear of the Headamp and restart the software.
• Check grounding – check Headamp board ground to case with lid off, otherwise all 6 screws and their contact points may need gentle cleaning – be careful with the board contact points, damage is possible here if no care is taken.

Real-World Examples

Single Channel Noise

This was resolved by cleaning all contact points for the Headamp and collector.

Deceptive problems – Noise Spikes

Be aware that not everything is always as it seems, this problem observed initially seems like a Headamp problem, after checking all ground issues and other problems mentioned in this section, I was still getting a regular spike across all channels. In the end; it turned out to be bad pressure regulation from the cylinder, dropping by 0.5Bar over a min then pulsing higher.