Turning on power instructions
From MariachiWiki
The order of turning things on is not important. What's important is to be very careful with a low DC (Direct Current) power supply for a detector. So let's start with it. The rest will follow:
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Powering on a scintillator detector (a black gun case).
The photomultiplier (PMT) is powered either by a separate low voltage power supply or by a coincidence box through a twisted pair of red/black wires. Never put more than 6V - you can damage the PMT inside the detector!
The low voltage power supply has two switches: one is to power on the unit itself and the other one is to provide a power to its consumers. So:
- Power on the unit first - the switch in the lower left corner of the unit face panel
- Make sure a voltage reading doesn't exceed 6V. With a KEPCO MSK 20-5M model the voltage is set by the left knob and read back on the left LCD display. With a KEPCO ABC model press "V Set" button to set and see the voltage you are going to deliver. Either set a new value using a keypad or press "Clear" button to stay with the current setting.
- Turn on the other switch to deliver this voltage to the detector. Depending on the model it is located either in the middle of the panel (a stand alone "DC OUT" red switch) or on a keypad (a top left "output on/off" button).
If you use a coincidence box with potentiometers:
- Decide what power line you are going to set voltage for by looking at numeric labels attached to wires.
- Fist time you set the voltage rotate a knob of a potentiometer (smooth metal cylinder inside the box) for this power line to the leftmost (counterclockwise) position.
- Put a dial switch to the number corresponding to the power line. It will connect a built-in voltmeter to this power line.
- Carefully rotate the potentiometer knob clockwise making sure that the voltage readings increase until you reach the desired voltage.
More details: there is a DC-DC converter inside the case which converts each 3V of input DC voltage to 500V on its output which feed a PMT. Putting more than 6V of low voltage you put more than 1000V(!) onto the PMT which is close to the maximum it can operate at.
NIM crate
There is a power switch on the right of the crate. You hear a noise of cooling fans when it's powered. You need to power the crate off if you want to add/remove any of modules inside.
Coincidence box
There is a switch inside the box. When it's powered on a red power led on the face panel is on. To be fully operational the box should be connected to a computer thru an USB cable and programmed by the computer. See more instructions on using the box here.
Oscilloscope
The oscilloscope has a power button too. A modern osciloscope is a computer and requires some time to boot, be paitient.
When done turn everything off
When you powering off the low voltage supply - do it the opposite order: cut the power to the detector first with the button in the center then the turn off the unit itself. The order of turning off other devices is not important.
