NEC ACT chassis populated with 7 modules.
NEC’s ACT (AccelNET Control Technology) is a modular data acquisition system designed to meet the needs of modern accelerator equipment. This system interfaces power supplies, controllers, and other beamline items with NEC’s AccelNET control software to provide a complete computer control system for NEC accelerators. Since 2009, all new computer-controlled NEC accelerators include ACT.
Existing NEC accelerators with computer control can be upgraded to use the ACT system as a replacement for the original CAMAC system. In addition, most manually controlled accelerators can be upgraded to computer control with the integration of ACT and the NEC AccelNET Control system.
The ACT system consists of a base chassis populated with up to 8 modules. The rear panel is customized and contains base plates containing the connectors needed for the application. The system offers a choice of four types of data acquisition modules: analog input, analog output, digital input, and digital output, as well as various connector types such as D-sub and BNC.
The base chassis accommodates a wide range power input (100-250 VAC at 50/60 Hz) and is fan cooled with over temperature protection. Additional hardware safety interlocking can be built into each chassis, such as contact closures and status signals up to 24 VDC. Hardware interlocking can be extended into the AC power distribution system if provided by NEC. Units are connected to a control computer running NEC’s AccelNET software via a proprietary bus.
A total of six different analog modules are offered that include transient protected inputs or outputs for system configuration. Each input channel uses a separate A/D converter (ADC), while a separate D/A converter (DAC) is used for each output channel. Additionally, the ADC contains a filter that is used to reduce AC line noise.
Each module has front panel test points and an on-board calibration table. The front panel channel LED brightness is proportional to the input/output voltage. These functions allow for troubleshooting by the customer or NEC technicians.
Each analog channel’s gain and unipolar/bipolar mode can be independently set. The channels are continuously updated with digital values and stored in the internal memory. The internal memory may be read at any time by the host computer.
| Unipolar Ranges | Biopolar Ranges | |
| Analog
Output 16 bit DAC |
10V
5V |
10V
5V 2.5V |
| Analog
Input 16 bit ADC |
10V
5V 2.5V 1.25V |
10V
5V 2.5V 1.25V |
Similar to the Analog Modules, six different input and output modules can be included to provide flexibility for system configuration. These modules have optically isolated inputs/ outputs and include a front panel LED for each input/output.
The digital control modules have watchdog capability, so that if communication with the control software is ever disconnected, the outputs of the related power supplies will stop. This occurs within seconds and may be programmed differently per channel.
NEC designed the ACT System for maximum flexibility. Number and type of channels can be selected for your specific requirements. Each chassis can hold up to 8 modules.
| Analog/Digital | Input/Output | Total No. of Channels | Features |
| Analog | Input | 16 |
|
| Analog | Input | 24 | |
| Analog | Input/Output | 16 in
8 out |
|
| Analog | Output | 16 | |
| Analog | Output | 24 | |
| Analog | Input/Output | 16 in
8 out |
|
| Digital | Input | 16 |
|
| Digital | Input | 24 | |
| Digital | Input/Output | 16 in
8 out |
|
| Digital | Output | 16 | |
| Digital | Output | 24 | |
| Digital | Input/Output | 16 in
8 out |
*Top: Analog 24 channel input board Bottom: Digital 16 channel output board
Contact NEC with any questions about the ACT System.
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