SIGNA™ Hero 3.0T Service Methods
5852800-8EN Revision 1.0
Object ID: 00000018WIA30840F20GYZ
Topic ID: id_13106360 Version: 2.13
Date: Jul 13, 2021 7:09:35 PM

High Order Eddy Current (HOEC) Calibration

Prerequisites

Table 1. Personnel requirements
Required persons	Preliminary requirements	Procedure	Finalization
1	Not Applicable	60 minutes	10 minutes

Table 2. Tools and test equipment
Item	Quantity	Effectivity	Part number	Manufacturer
LV SHIM PHANTOM INNER SPERE	1	-	2274476	-
LV PHANTOM SMALL HALF ASM	1	-	2306642	-
LV PHANTOM BIG HALF ASM	1	-	2306645	-

Table 3. Safety

Warning

Poison Hazard!

Green Phantoms contain nickel, a suspected carcinogen.

Do not ingest. dispose of as hazardous waste according to state and federal regulations.

Warning

Poison Hazard!

Pink phantoms contain silicon oil.

Do not ingest. dispose of as hazardous waste according to state and federal regulations.

Table 4. Required conditions
Condition	Reference	Effectivity
Confirm that Grafidy Eddy Current Calibration is complete	Grafidy Eddy Current Calibration	-
Remove all coils from the cradle and phantoms from the bore.	-	-

About this task

Use the High Order Eddy Current (HOEC) procedure to characterize the time dependent magnetic field errors in the bore up to at least the third order. This calibration works in conjunction with Grafidy Eddy Current Calibration, which adjusts and compensates the short, long, and very long time constant eddy currents for both linear and B0 terms. Run the HOEC calibration anytime after Grafidy is run.

Topic ID: id_SL5429338-1213178

Running HOEC

Procedure

Confirm that all three axis are selected (screen default) Figure 1.
In the HOEC window, select Scan.

In the status window, the tool displays the message that the analysis is complete for each axis (x, y, and z).

If the tool completed the analysis for all three axes, exit the tool. If the tool did not complete the analysis, review the error log for possible system issues.


This control:	Does this:
Expert Mode button	Allows you to view the images analyzed by the tool. (This is primarily used to look for sources of error.) Use Expert Mode only if directed to do so by OLC.
Gradient X/Y/Z boxes	By default, all three of these boxes are checked. When one of these boxes is checked, that gradient is included in the HOEC calibration.
Select Scanned File button	Click this button to select the results file from a previous HOEC calibration.
Re-Analyse button	Click this button to reanalyze the results file from a previous HOEC calibration. You must select a scanned file before clicking this button.
Scan button	Starts the HOEC calibration.
Abort button	Stops the HOEC calibration.
Exit button	Closes the HOEC calibration tool.

Topic ID: id_14965550

Finalization

Procedure

Remove any phantoms from the bore.
Perform SaveInfo.
Perform Check Scan before turning the system over to the customer.