NFA-06.11 Multidisc Neutron Velocity Selector Controller
Mains switch, fuses, lamps, front panel controls
NVS Selector body equipped with
Positioning Stand equipped with
The NVSIF-04-41 Standing Interface Unit collects and sends signals from the standing-related devices to the NVSIF-02 Selector Interface Unit, which collects signals from the selector body sensors and also controls actuating units. It is connected to the NFA-06.11 Selector Controller by several cables of 10 m length.
Control of the rotation speed with accuracy better than ± 2 rpm.
Several safety functions are considered to prevent failures in operation or damage to the selector. In case of emergency, i.e. failure of any function of the selector, the monitor stages disables AC Motor Driver Unit in order to stop the rotation.
The vacuum level is measured and displayed. If vacuum is worse than the preset value (typically 10 mbar), rotation is disabled.
The temperature of the bearings on both sides of the rotor is measured and displayed. If temperature is higher than the preset value, rotation is disabled.
The noise and vibration of the bearings on both sides of the rotor are measured and displayed. If noise and vibration are higher than the preset value, rotation is disabled.
Two independent revolution sensors are mounted; one in the motor, the other on the selector-rotor side. Both sensors give input signal for the rotation speed limiter. If speed is higher than the preset value, rotation is disabled.
Two kind of limit value monitoring and disabling is realized. These operate independently of each other.
Software: Program running in UD 70 Option module monitors measured values and disables rotating in case of trips.
NVSIF-01-41 Standing Interface Unit Receives, forms the angle encoder and end position switch signals and transmits them to NVSIF-02. Receives pneumatic switch and angle set motor control signals.
NVSIF-02 Selector Interface Unit has built in hardware limit monitors. Setting and measurement of selector tilt angle is realized by means of an angle set motor, pneumatic valve and angle encoder. It
Transmits data for NFA-06.11 Selector Controller
Trip units of NVSIF-02 monitors temperature, vibration, vacuum signals. Logic circuit collects trip outputs and over current bit of angle set motor driver circuit. In normal operation, output relay contact is closed, enabling AC Motor Driver UNI 1205 to operate. In case of trip threshold, output relay contact is opened disabling AC Motor Driver, and switches off +5V front panel Led.
3. NFA-06.11 Selector Controller
UNI 1205 type AC Motor Driver has a built in controller, with analogue and digital inputs/outputs. Two modules are supplied:
This controller realizes the measurement, control and safety functions by means of a built-in firmware in UD 70 Option module.
Input three phase line voltage is connected to L1, L2, L3 and earth point of UNI 1205 Driver Unit through mains switch, fuses, and FLT 3010 Mains Filter Unit. A brake resistor with heat sensor switch (bimetal) is also connected to UNI 1205.
The AC motor is connected via MOTOR connector with shielded motor cable.
A distributor card realizes the connection to front panel controls, to NVSIF-02 Selector Interface Unit, to AC motor rotation sensor, to host computer RS 485 communication port.
Rotation speed of both the motor and the selector rotor is measured. The optical revolution number sensor on the driver motor shaft gives 1024 pulses per revolution. The magnetic revolution sensor on rotor shaft gives 32 pulses per revolution. The motor side revolution signals are led to the Encoder input of the UNI 1205 type AC Motor Driver and rotor side revolution signals are led to the NVSIF 02 type Interface module. The pulses of revolution sensors are counted by the built-in microcontroller consisting of UNI 1205 and displayed by the host computer and on the display of NVSIF-02.
The same way, the microcontroller forms the control signals for the power stage on the principle of PID algorithm. The power stage of UNI 1205 controls the frequency and the voltage of the motor.
If the rotation speed of the motor becomes too high (limit value can be set by the host computer) the rotation speed limit monitor stops the rotating. NVSIF-02 as a hardware limit monitor also stops rotation if speed exceeds hardware limit value.
3.2 Measuring Bearing Temperature and Vibrations
Bearings and their temperature and vibration are continuously monitored. There are two temperature & vibration sensing circuit, type TMPACC-02 built-in the bearing housings. These are connected to NVSIF-02 through vacuum-tight connectors. Temperature and vibration signals are led to the inputs of an analogue multiplexer in NVSIF-02.
Conditioned analogue signals (temperature, vibration) are led to microcontroller analogue inputs through 0-20 mA current loops. Microcontroller monitors the temperature and vibration signals, NVSIF-02 and host computer can display the values.
Limit values can be set by NVSIF-02 and also by the host computer. If the temperature or vibration is higher than the limit value, NVSIF-02 or microcontroller stops rotation.
3.3 Vacuum Measurement and Displaying
The selector disks are rotating in vacuum. So the vacuum level has to be measured. The air friction of the disks was studied by varying the pressure in the vacuum housing and it was established that below 10 hPa (10 mbar) the power requirement is practically independent of the pressure. It is advisable to set the limit to this level although the pressure may decrease even below 1 hPa (1 mbar). Micro controller monitors the output of the Edwards type APG-M-NW16 Active Pirani Gauge through NVSIF-02 Selector Interface Unit. NVSIF-02 and the host computer display the value. The host computer can set the software limit value. If the measured vacuum is higher than the limit value, microcontroller stops rotation. Hardware limit can be set on the vacuum gauge manually.
3.4 Measurements and Control of Rotor Tilt Angle
The NVSIF-02 Selector Interface unit receives the signals coming from the rotor tilt angle sensor of type ANDIMIK-I-04-900-0 through NVSIF-01-41 Standing Interface Unit. Tilt angle signals are connected to the inputs of UD51 module of UNI 1205. Incremental type angle encoder is located at the base of the standing. The encoder and its processing has a resolution of 0.1o. By using the reference pulse appears on the same (zero) position the unit is able to compute the absolute angular position calibrated each time the selector body is crossing the zero position. That is the reason the automatic zero position searching is needed. The microcontroller in UNI-1205 receives the encoder pulses through UD51 module, stores the angle value in non-volatile memory, and receives the angle set motor over current signal from NVSIF-02, if it occurs.
Setting the rotor tilt angle: NVSIF-02 controls the DC servomotor on the positioning stand to turn the selector body to the required position automatically. It receives signals of the end position switches, displays their end position, when reached, and sends their state to the microcontroller.
Power: max. 2 kW
Bearing temperature measurement
Tilt angle setting
Tilt angle measurement
Vacuum pressure measurement
System safety limits stored in non-volatile memory
Dimensions of controller
Operating temperature: 10 to 50 °C
Weight: 5 kg
Distance between control unit and selector: max. 10 m
The selector controller has to be placed outside the radiation shielding. The distance allowed between the mechanism and controller is max. 10 m. The delivered mechanism and the electronics are connected via cables. The system needs 3 phase mains of a nominal 208/120V (50-60Hz) with protective ground. The MS-CAB1 cable is for the connection of the electronic unit to mains. The controller and the host computer should be connected via RS-CAB1 cable.
See the annexed cable connections scheme for the layout arrangement of the electrical part of selector.
Before operating the NFA-06.11, be sure that the mains voltage is 208V/50-60 Hz, 3 phases.
Connect the MS-CAB1 cable to mains, mains switch on the front panel should be in off state, levers of fuse and earth leakage switch should be in upright position.
Front panel switch positions should be: stop and aut
Connect the control electronics to the selector mechanism with motor (MT-CAB1), interface (IF-CAB1), interface mains (MS-CAB2) and ME-CAB1 motor-encoder cables.
Connect the vacuum pump to the vacuum flange.
Connect the air supply to the pneumatic input of the stand.
Connect the connector RS-485 to the host computer with RS-CAB1 cable.
Make sure that all the cables on the positioning stand are connected to Stand Interface NVSIF-01-41.
Make sure that motor-side, rotor-side sensor cables, vacuum sensor cable, standing interface cable and controller interface cable are connected to Selector Interface Unit NVSIF-02. (Refer to the attached Wiring diagram.)
With the shipped control electronics, three different operating modes are available: manual, automatic and remote operation.
In all of the three operating modes, UD70 Option module (PLC) in UNI 1205 unit implements the measurement, control and safety functions by means of a previously uploaded operating software, NVSSoft 2.1.
UD70 Option Module is supplied with uploadable software. In case of software damage or malfunction caused by e.g. a lightning, you can upload the software again according to the following procedure. Practically, this kind of fault is very rare.
Copy the following files onto your system partition (this should be C:) of your host computer, into a new folder (named NVS_Soft) from the compact disk supplied with the electronics:
Create NVS_1 subfolder in the previously created NVS_Soft folder, and copy Node_1.bin file to this directory.
Make sure, that NFA-06.11 Control Electronics is connected to your computer through RS 485 connection.
Run Winflash.exe from your hard disk
Wait while system program is loading; this can take some time.
Choose "Download a system file" command from menu.
Specify "C:\NVS_Soft\NVS_1\Ud70os.sys" as file name. Choose the appropriate serial port (RS 485). Click OK to start downloading.
Executing program downloading:
Choose "Download a compiled program" command from menu.
Specify "C:\NVS_Soft\NVS_1\Node_1.bin" as file name. Choose the appropriate serial port (RS 485). Click OK to start downloading.
This operating mode is used only to control the operation of the hardware. In this mode there is no communication with the host computer. UNI 1205 uses its own pre-set and stored parameters to control the AC motor.
Motor and motor control parameters are stored in UNI 1205 non-volatile memory. These parameters are separated in menu tables from Mem 0 to Mem 20, (See Unidrive User Guide for reference) and can be seen or downloaded by means of UNISOFT 3.1 software. UNISOFT 3.1 installed on the host computer can communicate with the module through an RS 485 connection. The operating software running in UD70 uses motor parameters stored in UNI1205 in its control process.
Switch on the MAINS. L1, L2, L3 lamp starts to light indicating the different line voltages; operating software in UNI 1205 begins to run using its pre-programmed parameters; on the upper part of its display of UNI 1205 “0”shows up, while “rdy” on the lower part. (This is the general starting sequence.)
By means of the RPM SET helipot you can pre-set the desired rpm value. Helipot conversion factor: 10000 rpm = 1000.
Then switch the right switch to MAN. Switching the left switch to START, AC Motor Driver begins to rotate the motor by the pre-programmed acceleration. You can read the actual torque and speed values on the analogue meters on the Selector Interface Unit. The speed value, as default, can also be seen on the upper part of UNI 1205 display. The lower part of the display shows “run”. Turning the left switch to STOP position, “run” changes to “dec” until rotation stops.
In this mode, it is only NVSIF-02 Interface Unit to communicate with UNI 1205. It measures both sides’ bearing temperatures and vibration, vacuum, and rotor speed. You can overview these values by turning the front panel switch of NSIF-02 to the appropriate position. There are hardware limit monitors built-in for temperature, vacuum, vibration, over speed. If temperature, vibration, etc. exceeds the preset values, the Selector Interface Unit stops rotation, disabling UNI 1205. In this case, the upper part of the UNI 1205 display shows “inh”.
In this operating mode UD70 PLC module in UNI 1205 implements the measurement, control and safety functions by means of the previously downloaded operating software, NVS_2.1. However, disabling functions of NVSIF-02 Interface Unit do not change.
Since a computer program, SystemWise 2.2; controls automatic operation so you have to install it in your host computer. This program gives you a graphic user interface of several panels. On these panels, you can easily control the process.
It is important, that the operating software should be running in UD70 PLC of UNI 1205, because Systemwise 2.2 running in the host computer can only communicate with the PLC through RS 485 serial link. Software limit values are stored in the non-volatile memory of UD70.
If serial communication is failed, UNI 1205 continues to operate with its preprogrammed parameters until the pre-set running time is ended.
Note: The controller front panel switches should be in AUT and STOP position.
Set-up of SystemWise 2.2
SystemWise 2.2 runs under Windows 95/98.
Place the software CD supplied with the electronics into your CD-ROM drive and run SETUP program from SystemWise folder. Setup wizard will create a SYSWISE folder on the system partition of your hard disk. During the steps of installation, choose RS 485 for protocol, 4800 bps for baud rate, and specify the communication port of the computer to be used for connection to the controller.
Create NVS_Soft folder in the root. (If you have not created yet)
Copy the NVSSOFT 2.1 data files to this folder from the supplied installation disc. SystemWise will use these files to create the appropriate panels, and control system parameters.
Using SystemWise with NVSSOFT 2.1
Run SystemWise on the host computer.
SystemWise startup dialog box appears on the screen. Select Open an existing panel layout box, and then click OK button. In the appearing dialog box choose C:\NVS_Soft folder and click on nvs_1.ctp file, then OK. Nvs_1.ctp file contains the control program.
SystemWise will load the panels.
The default is the ANALOGUE MEASUREMENTS panel; this will appear first, when the program is started. After the controller electronics starts up, click OFFLINE caption in the upper left corner of the screen; it changes to ONLINE, and the computer and the UNI 1205 unit links.
Note: You can exit SystemWise only in OFFLINE mode.
UNI 1205 sends measured data (limit values, angle etc.) to the program, and they are displayed in the appropriate boxes of the panels. There are five panels
White buttons are located on the bottom of the screen. Click to any of them to change screen.
Throughout the panels, there are two types of gray boxes: simple ones and boxes with arrows. Data appears in simple boxes, and limit values in the others. You can change them by clicking the arrows between two pre limits. There is a continuous communication, controller sends data, receives commands, host computer continuously receives data, and sends commands, if user initiates.
There is a button on the bottom of every panel, EMERGENCY. If clicked, the controller immediately stops rotating the selector or angle setting process, the EMERGENCY lamp on the WORK-FAULT screen, and the FAULT lamp on the lower right corner of the other panels changes to red.
You can run SystemWise from command line. See SystemWise online help.
In this operating mode the system can be controlled by an external data acquisition system. Connection can be made on a serial communication.
By means of an ANSI protocol through the RS 485 interface (see enclosed uniopt3.pdf) you can read the most important measured data, parameters, limit values, and can write in data, and commands to control the process.
The NFA-06.11 Selector Controller is operated from 208V/50-60 Hz, three phase mains supply, therefore when operating, the appropriate instructions should be considered:
WARNING: Covers of NFA-06.11 can be removed only after disconnecting it from the mains! When installing the system, it is the last step to connect the instrument to the mains.
The most important instructions and technical details necessary to the maintenance of the electronic controller are to be found in the following manuals:
If a malfunction is detected or at least after each 5000 working hours, the selector system has to be subjected to the same calibration procedure described in “Quality Control Report” as the last day test.
Electronic part of the selector system practically needs no maintenance, except for periodical dusting.