User manual: Undulator device
Status:
The first move after the RackPower has been turned on, results in a wrong move. It first moves to the backlash position, but then it just starts running out instead of going to the set position. It stops by itself, because the brake is turned on, causing a manual stop of the motors. It is necessary to send a Reset to the Device for new movements. After this first trouble everything seems OK.
980724 JSN
The Undulator device is completed and running.
990409 JSN
Contents:
- Undulator versions
- Overview
- Device parameters
- Device configuration
- Description of ASTRID undulator setup.
Overview:
The undulator position is controlled by two stepmotors (VRDM 5913/50 LNC (2A 1 ohm) and two stepmotor controllers (SDP 5-52) from Berger Lahr. To have a precise and certain knowledge of the positions two encoders from TReletronic (AE 100M) are connected directly to the thread driving the two magnet assemblies. By knowing the step number per turn, the thread pitch, and the positions for one set of encoder values the gap can be calculated from the encoder values.
To ensure good reproducibility the gap can first be moved to a position a little larger
(controlled by parameters in the Console), and then moved to the desired value.
Device parameters:
For addressDefinition the device uses AddTypeId number 9 (One-dim address) which uses a0 to determine the parameter number.
parameter |
Suggested |
Parameter name |
Data Type |
Interpretation |
Comment |
0 |
gap1set |
gap 1 setvalue [mm] |
Unipolar Float |
Undulator Position (ID 129). |
. |
1 |
gap2set |
gap 2 setvalue [mm] |
Float |
. |
Only in use when running with tapered gap. Otherwise automatic set to same value as gap1set |
2 |
gap1 |
gap 1 read [mm] |
Float |
. |
. |
3 |
gap2 |
gap 2 read [mm] |
Float |
. |
. |
4 |
encoder1 |
encoder 1 read |
Unipolar Float |
. |
in steps |
5 |
encoder2 |
encoder 2 read |
Unipolar Float |
. |
in steps |
6 |
tapered |
tapered gap |
Control bit |
. |
. |
7 |
reset |
Resets the controller |
(pulsed control bit) |
. |
Writing a one to this parameter will reset the device. This should not be nesserary very often, and should properly be a restricted parameter. |
8 |
error |
Error number |
Word |
. |
A 0 indicated all is OK, 9 that the undulator is moving, and anything that something is wrong. |
9 |
errStr |
Error String |
String |
. |
Tekst string with error. |
10 |
move |
move undulatorgap |
Control bit |
. |
Initiates a movement of the undulator gap. Is high as long as the undulator is moving. |
11 |
backlash |
Backlash |
Control bit |
. |
Used to turn on and off whether backlash movement is enabled or not |
12 |
blashSize |
Backlash Size |
Float |
. |
The value of the backlash. |
13 |
moveFast |
move undulatorgap fast |
Control bit |
. |
Initiates a fast movement of the undulator gap. Is high as long as the undulator is moving. |
14 | DeActivateBrake | Deactivation of the brake | Control bit | On/off control bit (ID 517) | When set the brake is disengaged, which allows faster undulator movement. Automatically reset after 10 sec of inactivity. |
15 |
moveSlow |
move undulatorgap slow |
Control bit |
. |
Initiates a slow movement of the undulator gap. Is high as long as the undulator is moving. |
16 | moveInhibited | moveInhibited | Control bit (on/off) | On/off control bit (ID 517) | Inhibits the undulator movement when set. (To prevent movement during injections) |
Related parameters:
For the ASTRID undulator is there also some parameters controlled by G64. (see also Description of setup)
Parameter |
Surname |
Description |
UND21CON |
brake |
Bit control for the brake. Has to be disengaged (low) for the undulator to be able to move. |
brake_S |
Bit status for the brake. (The brake can also be engaged by interlock.) |
|
Neg_Limit_01 |
Negative limit switch for motor 1. Low bit is ok |
|
Pos_Limit_01 |
Positive limit switch for motor 1. Low bit is ok |
|
Neg_Limit_02 |
Negative limit switch for motor 2. Low bit is ok |
|
Pos_Limit_02 |
Positive limit switch for motor 2. Low bit is ok |
|
RPC12REL |
Rack_Power |
Rack power for all the undulator control. |
Power |
Rack power status. |
Device configuration:
The following parameters are setup by the ConsysManager and stored in the .config file at the front-end computer on which the device is loaded:
- The calibration positions and the encoder values at the calibration positions.
Encoder 1: 421457 at 50.00 mm
Encoder 2: 499985 at 300.00 mm - COM-Ports: The serial port number for the 2 stepmotor controllers and the 2 encoders.
Encoder 1: COM3
Encoder 2: COM4
Controller 1: COM5
Controller 2: COM6 - Baud-rate: The baud-rate used to communicate with the controllers and the encoders.
Encoders: 2400 baud, (7 bit, even, two stop)
Controllers: 9600 baud, (7 bit, even, one stop) - The maximum and the minimum gap (350 mm and 25 mm).
- The maximum gap difference (4 mm).
- The maximum allowed gap difference for non-tapered operation (0.5 mm).
- Backlash size (0.5 mm) (default value for parameter 12)
- The motor speed (2500 (step/sec))
- The fast motor speed (10000 (step/sec))
- The slow motor speed (500 (step/sec))
- The motor acceleration (25 (step/sec/msec))
The values given are as of 971212 (JSN).
010320: Change of motor speed from 10000 to 2500 and acceleration from 50 to 25.
Description of ASTRID undulator setup:
For control of the undulator a special electronics box has been made (Poul Aggerholm), which takes care of all the interlocks, and interfacing to the G64 parameters. There is a brake for each motor. This has to be disengaged before the motors can be moved. Both the emergency switches and the G64 parameter (UND21CON.brake) has to be on. Furthermore is there an interlock for the limit swithces.
Last Modified 29 March 2019