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QXi Notes
Term | Definition |
---|---|
GOC3 Console includes | HP-8000 CPU, one SDDA with 2 scan disks and Intercom, one DARC, one IG. |
GOC4 Console includes | HP-8200 CPU, a DARC 2 that contains both scan disks, one IG module, and the Intercom Unit at the far left. |
STC | Stationary Controller Junction for all stationary electronic signals |
Stationary E-Stop | Disconnects all power to gantry when activated |
STC Power Supply | Supplies Power for STC |
Hoist | Used for removal of components & service |
Tilt Potentiometer & Limit Switches (behind sheet metal) | Gives Tilt Angular Positioning +/- 30° Tilt Angle Limits Provides tilt position feedback |
Hydraulic Cylinder | Provides tilting movement |
Power Pan | Gantry Incoming Power “Bulkhead” Main hook-up location for installation Filters Incoming Power |
Tilt Relay Board | Tilt Positioning Controller (Back, Forward, Enable) |
Hydraulic Pump | Fluid Power Source |
Hydraulic Mount | Supports Hydraulic Cylinders Fixed to Stationary Base |
What is ig board? | a power pc board with a rac (recon accelerator) board piggybacked onto it to speed up back projection. |
troubleshooting ig problems | in the darc /var/log/messages might list "ig1 down", and this would be a bad ig board. if the lan led is not blinking, it is either the darc or the cable. |
How can you see IG boot up | if you attach a 15 pin male (both ends) cable from either monitor to the ig, and recycled ig power (it takes about a minute) then you can watch the ig board boot up. |
IG Node Ping | {ctuser@hostname} su - Password: <password> #bigguy [root@hostname]# rsh darc Last login: Mon Aug 6 19:35:00 from oc You have new mail. [root@darc ~]# ping ig1 (or ig2 or ig3 as applicable) |
Main data flow of the DARC2 node | Receive raw data from the Gantry Store the raw data to the scan data disks Restore the raw data from the scan data disks and transfer to IG nodes over GB Ethernet.Take multi-image streams from the IG nodes and forward them to the host computer |
How can you clean the reconstruction queue? | use the command 'cleanq' |
What does reset or regenerate database do? | cleans all the raw data; therefore, need to make sure customer do all recon they need to do before clean the raw data. |
Thermostat | Controls Switch point of Gantry Fans |
What voltage is used by the axial drive board to rotate the gantry at the prescribed speeds, or position it for scout scans and turning on the alignment lights? | 440 Vac 3 phase power |
How does axial motor rotation stop? | the motor current is pulled from the motor, through the axial drive board, and through the dynamic brake assembly. |
What will be energized when the gantry is at position for scouts and the alignment lights to hold the gantry stationary? | the brake |
What can be used to determine the position and speed of the gantry? | the encoder that generates pulses |
What is azimuth detector? | once per every rotation, a small flag on the rotating section of the gantry interrupts an led that creates a pulse so the number of revolutions can be counted, and the 0 degree position can be tracked. |
_____________ is where all power signals come in and out of the system rotating gantry. 120AC and 700VAC. | Brush block |
What happens if more than two or three signal brushes break? | limit its performance. Signal corruption errors possible. Current passing through fewer connections, increases resistance and heat. |
What does convert the 3 phase 380 Vac at PDU which will be supplied to brush? | a diode bridge |
How do DAS data transger from transmitter to receiver? | by HSDCD Slip Ring |
What is the use of collimator in CT? | (I) varies the slice thickness of X-ray. (II) Moves a filter in and out with two configurations, head & body |
What is the function of HEMRC? | chops DC to AC for rotor motor and spin the anode target so we don’t melt a hole in it with the current making X-Ray |
What does on-board controller include? | COM board (comm’s back to STC Host via Slip Ring.) KV- control/measurment mA- control/measurment Rotor- control/measurment Gentry I/O – Interlock watchdog/timing mechanism. |
What is the function of inverter? | chop DC to AC for HV transformer primary |
What is the function of HV tank? | Step-up to 70 kV production for X-ray tube & provides mA & kV feedback |
What kind of voltage is supplied to X ray tube? | AC for the Rotor and DC for KV Potential on the Tube for creating X-Ray |
In HV generation, which component use HVDC? | inverter and HEMRC |
How HV tank primary gets AC from inverter and output DC for X ray tube potential? | AC feeds to a HV TANK primary – not a conventional transformer, but a stacked set of voltage doublers, comes out as HVDC – in which energy potential is applied to the Tube. AC for the Rotor, DC for the KV Potential on the Tube. |