E-Detector Motion System

Motion Mechanism

For moving the e-detector in running position or to garage, first open the GUI which can help us do it remotely

During standard running conditions, the above GUI at top left shows X = -8.6890. We park it to Garage whenever

when we expect beam to be re-tuned through the chicane after a beam studies or a long down
we are sure of not running for a couple of days at a stretch
when the beam is intended to be taken straight through (instead of the chicane)

The procedure for parking is:

The detector can be moved only when the beam is off.
Call MCC and request to mask Compton electron detector motion FSD. Make sure that they have masked before starting to move.
In the drop-down box on the left-middle of the e-detector motion GUI, choose 'GO HOME' You should start seeing the box indicating that the detector is moving gets highlighted by yellow.
Check to see that the motion is complete. You see the position readback to be X=0.0000 and the yellow highlighting is off.
From the same drop-down menu, now select the 'Garage' and the detector start going to Garage.
On completion of this motion again, the yellow highlighting goes away and the detector is well parked now.

This should preferably be done by an expert, or while you have been requested to do so by an expert

The beam is probably in Garage, when you start to move it in. Call MCC and get the Compton electron detector motion FSD masked
You can see two drop-down boxes on the middle left of the GUI. Click on the top drop-down box and select "Go HOME". The detector would start moving towards its predefined HOME position.
Once the previously initiated motion is complete (the yellow highlighting turns off), from the same drop-down menu select Go Pos 1. At HOME you can see X=0.0000 on the top left corner of the GUI.
The detector again starts moving further towards the beam (apologize for the GUI vertical view being counter-intuitive). The position reader would now show X=-8.289
Click on the 2nd drop-down box to select Jog Down 2mm. This would move the detector 2 mm further towards the beam.
Once the position starts showing X=-8.489 Repeat the above process again by selecting Jog Down 2mm in the drop-down box.
The position reader at top left of the GUI should be showing X=-8.689. YOUR ARE DONE!

Beam can be taken again.

The electron detector is connected to the QWAD using the custom made [Flex-cable]. The detector is placed inside the vacuum-can whereas the QWAD boards are connected from outside the vacuum-can using appropriate flanges used between the Flex-cable and the QWAD. The connection between e-detector and the QWAD (if the vacuum - can was transparent) can be depicted as in the attached picture.

The electron detector vacuum - can has a motion mechanism to allow us to move the detector vertically in and out of the beam along with the ability to rotate the detector facing the beam. A schematic view of the assembly can be seen here.

We are using a stepping motor identified as KML062S04 for vertical motion ( data sheet ) of detector using a MDC accuator ( specifications ). This motor is being controlled by a single axis IDC Controller (User Manual). The Motion Controller can be controlled through its keypad or via computer terminal after installing its software provided on their website

At EOT- (physically top most) the actuator position read back (as seen on the controller display) is

 -3.7833
 00000000      00000000

AC.02 VE.1 DA2 GO

 +2.0000
 00000000      00000000

AC.02 VE.1 DA1 GO

 +1.0000
 00000000      00000000

AC.02 VE.1 DA-2 GO

 -2.0000
 00000000      00000000

AC.02 VE.1 DI1 GO

 -1.0000
 00000000      00000000

We shall maintain two files for the controller settings

The list of programs loaded in the current configuration are