User Manual - NIM HV Detector Bias Supply
This manual was written as part of a student lab exercise in the KJM-FYS 5920 course at the University of Oslo in the autumn 2010.
Co-author (student): Martin
Lab supervisor: Hilde-Therese Nyhus (PhD-student)
Responsible teacher: Prof. Jon Petter Omtvedt
User Manual for NIM HV Detector Bias Supply
The HV-unit used in this exercise is a C.A.E.N Mod. N 470. It has 4 independent HV channels able to supply four output voltages from 0 up to ±8kV, in three different ranges: 0 to ±3kV / 3mA (max), ±3kV to ±4kV / 2mA (max), and ±4kV to ±8kV / 1mA (max). The polarity of a channel is showed by a LED on the front panel, and is changed by reversing the relevant diode bridge inside the unit.
The HV output connectors on the back panel are SHV type, all other connectors are LEMO 00 type.
All the operational parameters can be programmed via the front panel keyboard, and monitored on two alphanumeric displays on the front of the device.An operational parameter is changed by pressing F + function number + # + new setting + #. With some functions it is only nescessary to dial F + function number + #, like with the on and off functions.
The most important functions of the device, and also the functions used in this exercise are:
F 0: Choose channel (0-3)
F 1: Voltage
F 2: Current limiter
F 8: Ramp up (increase of voltage/sec)
F 10: Channel on
F 11: Channel off
Above the keyboard, there is an HV enable master switch. This switch allows one to enable or disable the HV of all the active channels simultaniously. It must be in the enabled position in order for the channel(s) to provide HV. The switch is secured such that one have to pull it outwards before it can be flipped.
There are also 9 LEDs on the front panel which shows the status of the selected channel.
3. OVC – Over current
4. OVV – Over voltage
5. UNV – Under voltage
7. RAMP UP
8. RAMP DOWN
9. MAXV – Max voltage