Technical Support Information No January Complementary Service Information for MicroSAM Part 4

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1 Process Analytics USA Customer Focus Page 1 of 7 Complementary Service Information for MicroSAM Part 4 According to the increasing number of MicroSAM applications and the experience resulting from it, following are the most recent service tips. Extension of the TCD lifetime For this purpose following adjustments are recommended: - Increase amplification (Gain) for all detectors to 4, better to 8 - TCD 1, 3 und 4: decrease bridge power to approx. 40mW - Operate TCD 2 with the least adjustable voltage (500mV) - Warning: the measured peaks shouldn t be truncated (over range) Example:

2 Process Analytics USA Customer Focus Page 2 of 7 The adjustments can be accomplished in the Application AO Table via the System Manager: Alternatively the adjustments can be made via the Maintenance Menu of the HMI:

3 Process Analytics USA Customer Focus Page 3 of 7 With a detector bridge power of approx. 40mW and a gain value of 8, an equal signal to noise ratio is achieved as if adjusted at 95mW and a gain value of 1: This is especially essential when using carrier gas helium and hydrogen. For the carrier gases nitrogen and argon the least adjustable bridge power should be applied (500mV). Special note for the SITRANS CV: According to the PTB certification, the TCD bridge power must be adjusted > 70 mw!

4 Process Analytics USA Customer Focus Page 4 of 7 Implementation of a "Shutdown"- Procedure for the MicroSAM GC Problem: If the carrier gas setpoint on EPC_1 falls lower than 20 kpa, then an internal deactivation of the temperature and pressure regulation is carried out. Via HMI respectively System Manager this deactivation is not identifiable (no mark up). Furthermore the analysis is not stopped and it is not apparent if the detectors are turned off. Solution: Once the current setpoint on EPC_1 falls lower than 20 kpa, a visual deactivation of all heater and pressure regulators is occurring according the Maxum shutdown procedure. The detectors are disconnected and they get asterisked. All applications go to HOLD, so a sample injection is avoided. For this purpose it is necessary to implement a monitoring procedure of the EPC_1 analog input with the ID 400, EPC_1 Meas using a limit and an alarmhandler table. By undershooting of the threshold of 20 kpa, a MaxBasic program gets executed which is performing the mentioned deactivations: Alarmhandler-table: The associated Limit-table: The program-table: The associated MaxBasic program can be found on the Intranet (internal service support).

5 Process Analytics USA Customer Focus Page 5 of 7 For those who are able to compile MaxBasic code, here is the source code: Sub Main() =================== 'Function: Turns off all applications, temp, press ctls and detectors 'Revision History Name Date Comments '4.1 Niko Benas 04/28/08 Monitoring EPC_1 via limit (< 20 kpa) ' =================== Dim sql As String Dim z As Long ' Put ALL Applications in HOLD sql = "Update application Set mode = 0" ' Disable ALL Temperature Controllers sql = "Update app_tempctl Set enable = false " ' Disable ALL Pressure Controllers sql = "Update app_pressctl Set pwmenwrite = false" ' Disable ALL Detectors sql = "Update app_detector Set bridge_enable_write = false" End Sub The analog-input which is scanned: Advantage: An injection in a cooling or cold MicroSAM GC is not possible anymore. Consequential damage to the analytical module is avoided.

6 Process Analytics USA Customer Focus Page 6 of 7 Implementation of a detector-filament-monitoring for the MicroSAM GC Problem: It is demanded that at the delivery status of an applied MicroSAM all detectors are turned off. Switched off or deactivated detectors are undetected by the user. Solution: Switched off or deactivated detectors (filaments) are pointed out via an error message (notice). This is accomplished through an implementation of a MaxBasic monitor program, which is monitoring the status of all detectors: The program-table: The program is time scheduled (every 5 minutes). A deactivated TCD is displayed with the error message "+ Filament TCD_x is disabled": The appropriate program_schedule - table: Advantage: An analysis where detectors (filaments) are deactivated and which can result to wrong results, doesn t stay undetected anymore:

7 Process Analytics USA Customer Focus Page 7 of 7 The associated MaxBasic program can be found on the Intranet (internal service support). For those who are able to compile MaxBasic code, here is the source code: Sub main() ========================== 'Function: 'This program generates an associated error message if it is found that a filament is disabled 'This program is time scheduled 'Revision History: Author Date Comment '4.1 Niko Benas 2008/05/09 'Arguments: Appl, Strm 'Variables Dim n As Long Dim SQL As String Dim Snap_Filament As Snapshot 'Get bridge_enable_write status from app_detector table ' SQL = "Select id, name, bridge_enable_write" SQL = SQL & " From app_detector" SQL = SQL & " Where application_id = " & Str$(appl) SQL = SQL & " Order By id " Set Snap_Filament = db.createsnapshot(sql) Snap_Filament.MoveFirst Do Until Snap_Filament.EOF 'MsgBox Snap_Filament(2) 'Check for Error If Snap_Filament(2) = "FALSE" Then 'Post alarm SQL = "Insert Into modbus_msg_buffer(id,anlz,application,stream,value,type) Values" SQL = SQL & "(0,997," & Str$(appl) & "," & Str$(strm) & ",'Filament" & Str$(Snap_Filament(1)) & " is disabled ',26)" n = db.executesql(sql) EndIf Snap_Filament.MoveNext Loop Snap_Filament.Close End Sub