Manually Entering Drifts

A drift check re-reads the known cylinder gas partway through the day (Noon) and at the end of the day (End-of-Day) to confirm the analyzer has not lost accuracy since the morning calibration. Like daily calibrations, drifts are usually captured by a SpanBox, but you can enter them by hand in Chateau on a computer or in Chateau Mobile on the handheld.

A drift always belongs to a daily calibration, so you must enter the daily calibration first (see Manually Entering Daily Calibration Confirmations). Each analyzer's Noon and End-of-Day drifts attach to that day's calibration for the same analyzer.

When you enter a drift in Chateau, you set Pass or Fail yourself. There is one exception: if the analyzer has calibration tolerances on file, Chateau evaluates your readings against them and stores the result it calculates rather than the one you picked. Tolerances reach Chateau by syncing from a SpanBox — there is no screen in Chateau for entering them by hand — so this applies to analyzers that have been used with a SpanBox. In Chateau Mobile you choose the result yourself too — the Input Drift Record screen has a Result: Pass / Fail control per cylinder, which simply defaults to Pass. This is the one calibration screen on the handheld that does: a daily calibration confirmation entered through Input Confirmation PPM has no such control and is always recorded as Passed.

Drift Method and Drift comparison method. These are two separate choices, and it helps to keep them straight:

Drift Method decides how many readings you take per cylinder — Standard (one reading), VVa (three readings), or VVa §60.485a (one reading, judged against the strictest requirement). Drift comparison method — labeled Drift To in Chateau Mobile — decides what the reading is compared against — the morning Confirmation PPM or the Cylinder PPM. You choose this yourself for Standard and VVa. For VVa §60.485a it is locked, because that method must pass against both the confirmation reading and the cylinder concentration.

Both live under Drift settings, which the dialog labels as applying to both the Noon and the EOD drift — changing one changes both. Pick the method your program requires when you enter the drift.

With VVa selected, Chateau records three readings per cylinder (Test 1–3) and the Drift % it shows for that cylinder is the average of them.

Entering in Chateau

1. Go to Resources > Calibrations > Daily Calibrations and open the daily calibration the drift belongs to (it must already be entered).
    
2. In the Add Calibration dialog, switch to the Noon Drift or EOD Drift tab. The Session details at the top — Analyzer, Technician and Probe Type — are shared by the daily cal and both of its drifts, as are the cylinders under Cylinders. As a shortcut, a session whose daily calibration has passed also shows + Noon Drift and + EOD Drift on its heading in the grid, which open the same dialog on that tab. Each button appears only while that drift is missing and disappears once it has been entered, leaving just the edit pen.
    
3. Set the drift time, then choose the Drift Method — Standard, VVa, or VVa §60.485a.
    
4. Choose the Drift comparison method — Confirmation PPM or Cylinder PPM. (On the handheld this field is labeled Drift To.) If you selected VVa §60.485a this is set for you and cannot be changed.
    
5. The cylinders from the daily calibration carry over. Enter the readings for each cylinder and mark them Pass or Fail. Standard and VVa §60.485a take one reading per cylinder. VVa takes three — Test 1, Test 2 and Test 3 — and you mark each one Pass or Fail on its own; the averaged deviation percentage is shown to help you make that call, but it is only there to guide you and is not the pass/fail decision.
    
6. Watch the Overall line at the bottom as you work. It reads In progress — 0 of 3 cylinders recorded until every cylinder has its readings, then Passed — 3 of 3 within tolerance. The total counts the cylinders on the session, so it goes up if you use + Add Cylinder. The Noon and End-of-Day drift each get their own Overall line, evaluated independently. You can add an optional comment beside it.
    
7. Click Save.

You can add the Noon drift and the End-of-Day drift at different times during the day; each is added from the same daily calibration session. Drifts on a calibration you entered manually can be edited later.

Entering in Chateau Mobile

Entering on the handheld requires a Bluetooth connection between the analyzer and the device running Chateau Mobile, and the daily calibration confirmation must already be entered. You can do it with or without a tour assigned to you.

1. Make sure you are connected to an analyzer and checked out. Open the main menu (top-left) and select Calibrations.
    
2. Tap Input Drift Record.
    
3. Enter the time, probe type, drift type (Noon or End-of-Day), and drift method (Standard or VVa), set Drift To to compare against the confirmation or the cylinder PPM, then tap Next.
    
4. On the Drift Test page, the cylinders from the daily calibration confirmation are selected automatically.
    
5. The analyzer's current reading appears in the Analyzer PPM field. Tap Record & Next to use it, or type a value in the Manual PPM field and tap Record & Next to use that instead.
    
6. Repeat for each cylinder. You can tap the PPM, date, and time in the grid to edit them.
    
7. Tap Save Drift.

The drift records become available in Chateau after you check in.

Editing a drift

A drift you entered manually can be corrected later from the daily calibration's session in the Daily Calibrations grid. Drifts that came from a SpanBox are locked and cannot be edited.

When you reopen a manually-entered record, Chateau warns you that changing readings recomputes Pass/Fail, and that if you change the calibration date or time you should re-verify the inspections that rely on that calibration — those inspections were validated against the original calibration, and moving it can change which ones it covers.

Changing the Drift Method on a saved drift. Because the Drift Method decides how many readings a drift holds, changing it on a drift you already saved will rewrite those readings. If you switch a three-reading VVa drift to Standard or VVa §60.485a, Chateau asks you to confirm first, and then clears Test 2 and Test 3 — those readings are removed, not just hidden. The change is recorded in the edit log. Remember that Drift Method is shared by the Noon and End-of-Day drift on the same session, so both are affected.

Viewing your drifts

Go to Resources > Calibrations > Daily Calibrations, choose a date range, and click Search. A daily calibration's session heading shows the Noon and End-of-Day drift status alongside the daily calibration, so you can see at a glance which drifts have been entered and whether they passed. See Daily Calibration Grid for more on the grid.