Precise waveform measurement of long pulses
and macropulses up to several milliseconds
with minimal droop and noise
Bandwidth < 3Hz to 1MHz | Resolution < 1.5 µArms |
The ACCT is an evolution of the active transformer first proposed by Hereward in 1960. Compared to the Hereward transformer, the ACCT presents much lower noise, a DC offset of the output reduced to a very small value and excellent long-term stability. The sensor is built with a single winding, which requires only one wire pair between sensor and electronics; this allows much better EMI rejection when long cables are used. The electronics circuit is multistage, implementing the best low-noise operational amplifier available for this application.
3 packaging types for the ACCT sensor In-flange ACCT is mounted in the beam line. Short axial length, includes a ceramic gap vacuum-brazed to kovar. Does not require bellows, wall current bypass nor electromagnetic shield. Available from CF3“3/8 to CF8“ |
 In-air ACCT installation, over the vacuum chamber Requires installation of a “gap” to prevent the wall current from flowing through the ACCT aperture. The gap can be a brazed ceramic ring or an organic material O-ring depending on the vacuum requirements. Typical installations include bellows, a wall current bypass and an electromagnetic shield enclosing the ACCT completely. |
 In-air ACCT with optional magnetic shield for high resolution measurement in noisy environment. Special shielding available on option |
ACCT electronics and cable | ||
ACCT Electronics output made to be read in high impedance devices. DIN-rail mountable Linear power supply available |
Cable from Sensor-to-Electronics is a shielded twisted pair (radiation tolerant on option) with BNO (twin BNC) connectors. |
Full scale range From Output full scale Bandwidth Noise at 10mA FS Noise at 100mA FS | ±10mA to ±2A ±10V 3Hz to 1MHz ≈1.5µArms <5µArms |
