Liquid Bearing Tube Service Tool Impact

1 General

This document describes Service Tool Impact when Optima CT680 Series and Optima CT670 system with Liquid Bearing Tube.

2 Liquid Bearing Tube Rotor management

Liquid Bearing Tube requires unique rotor management in order to prevent rotor damage. The followings are basic constraint of rotor management.

Gantry rotates 2sec./rev. when rotor acceleration starts. (Some Service Tools can rotor start without the rule as exception)
Rotor rotating speed is Low or High. When rotor rotates with High Speed and it decelerates to Low speed 20 mins, past after End exam event.

When rotor rotates with low Speed and it decelerates to coasting 7 mins, past after switching from high speed.
Rotor rotates continuously unless E-Off, HVDC Off, or some service tools execution.
Rotor acceleration is required manually when rotates gantry faster than 2 sec./rev. because it does not start automatically.

Dedicated rotor control tool for Service engineer was implemented to manipulate rotor start or stop in any time (Refer to Rotor Control Tool with LB Tube - Command or Rotor Control Tool with LB tube - GUI (20BW25.x or Later) for details).

And Liquid Bearing Tube unique gesyslog messages were also implemented (refer to gesyslog for Liquid Bearing Tube manual for details).

Refer to the following Table for each Service Tool impact.

Table 1. Service Tool impact by Liquid Bearing Tube
Service Tool Impact	Liquid Bearing Tube System
Generator Tool - JEDI	The information is posted to gesyslog message. Use rotor_ctrl -start command to start rotor.
Detailed Cal.	Gantry Balance is skipped.
Collimator Functional	Before the tool starts, use rotor_ctrl -start command to start rotor for high speed (1.0sec./rev. or faster) Gantry rotation.
Axial Functional	Before the tool starts, use rotor_ctrl -start command to start rotor for high speed (1.0sec./rev. or faster) Gantry rotation.
DAS Tools	Scan is aborted with gesyslog message at the following conditions. 1. Rotate Gantry faster than 2sec./rev. without rotor High speed. 2. Select Rotor Off at Option setting with Gantry rotation faster than 2sec./rev. 3. X-ray Off scan (0mA scan) with Gantry rotation faster than 2sec./rev. Check gesyslog message when scan is aborted. Check gesyslog message when scan is aborted. Note: Option setting of rotor on/off is ignored at Auto Test.
Scan Data Path	Rotor becomes high speed at any combination of Scan protocol automatically.
DDC	Scan is aborted with gesyslog message at the following conditions. 1. Rotate Gantry faster than 2sec./rev. without rotor High speed. 2. Select Rotor RxOverrides Off setting with Gantry rotation faster than 2sec./rev. 3. X-ray Off scan (0mA scan) with Gantry rotation faster than 2sec./rev. This scan can be available by setting Rotor RxOverrides to ON. Check gesyslog message when scan is aborted. Error: 260100193 Gantry rotation of faster than 2.0 sec/rot was requested although Liquid Bearing tube rotor is not rotating. Rejected the request because it will do fatal damage to the tube.
Gantry Service Balance	The tool can't start up without using rotor_ctrl -start command to start rotor for high speed (1.0sec./rev. or faster) Gantry rotation. Use rotor_ctrl -start tool to start rotor at first.
Flash Download	The tool starts and aborted when rotor is rotating. Stop rotor by using rotor_ctrl -stop command when "update" is executed.
Cold ISO, Tube Alignment	Filament Cal., HHS Scan and Hot ISO has been moved after Gantry Cover Installation in order to prevent “Hot landing” of X-ray Tube rotor.
Other Service impact	Liquid Bearing Tube System
Gantry Service Switch Panel	1. Rotation speed at "Manual high speed" become 2sec./rev. 2. It's recommended to wait before turning off HVDC or 120VAC if X-ray tube is hot. When Hot ISO, heat soak or Detail cal are done, they bring the tube to full hot and need to waiting until the casing is cool.
System Reset	If perform CSD->System reset. This function may stop Tube Rotor, recommend to waiting before proceeding since the TubeCare indicator is in the Green Zone.
System shutdown	Rotor rotates 5 mins continuously (low speed) after system shutdown, and High Voltage for HV system is alive. Be careful when turn off HVDC or 120VAC, refer to Service impact about Gantry Service Switch panel.
System Restart	Rotor will stop during system restart process, after app start, rotor will start to High speed automatically.
CleanMon	Tube rotor will stop after 7 + 5 min.
st	Rotor will stop during Jedi reset when application startup.
LFC	The following pop-up message is displayed during start up. Tube Identification not detected. Please contact Service. Scanning is permitted.

3 SWHWINFO / CHECK_CONFIG

The following shows the comparison of Tube type and example.

Liquid Bearing: Perenna

Example:

{ctuser@bay}[1] swhwinfo <Enter>
20BW25.5.H40_PN_CM64_G_GMV (Liquid Bearing Tube)
{ctuser@bay}[2]

4 Tube rotor damage prevention

Follow to the procedure Liquid Bearing Tube Rotor Control Thermal Guidance for Hot landing prevention to prevent X-ray Tube rotor damage.

5 Pop-up message for Hot landing prevention

Using some service tools will stop the rotor (See Table 2). The following pop-up will appear, this is to inform service personnel that recommended waiting time to stop the tube rotor if tube is in “Green” temperature zone. Refer to the Figure 1 in case of pop-up appears.

Table 2. Tool list with attention pop-up
Service Tool (Refer to the list below for affected sub-menu)	Sub menu
Gen Tool	No Load KV in kV Diagnostics Inverter Short Circuit in kV Diagnostics Heater Diagnostics Initialize Database Save Runtime Parameters Restore Runtime Parameters
DDC	Static X-ray off with rotor override default Static X-ray off with rotor override off Rotating X-ray off with rotor override default Rotating X-ray off with rotor override off
System Reset	Scan
DAS Tool	Auto Test Pop Noise & Micro with Rotor Off Rotating Noise in Manual Test with Rotor Off Plateau Noise Manual test DC Noise Offset in Manual test