Shift Taker

Two power supplies crates are being used to power the top and bottom volumes of the Silicon VertexTracker (SVT).

To connect to their interfaces, first login into clon10 from a JLab machine with the user name clasrun:

> ssh clasrun@clon10

In order to obtain the password, talk to an expert!

At this point, the EPICS GUI is started as follows:

> medm -x /usr/local/clas/devel/R3.14.12/support/xycomioc-1.0/medm/svt_trips.adl

Turning power ON

Make sure that the box to the right of the OFF/ON buttons are RED.

To turn on the low voltage power (DVDD, AVDD and V125) and the high voltage bias click the ON button next to the hybrid you want to power.

Note: there is often a very significant delay before the GUI updates after a change so be patient.

You should see currents on DVDD (~250mA) and AVDD(~350mA but sometimes ~500mA). The current on V125 will often be zero until the DAQ has configured the chips. The bias should ramp up and you should see it stopping at 180V.

One special feature is that the DVDD power is coupled between two hybrids (0&1,2&3, and so on). Thus you will see DVDD current of the other hybrid ON even though that hybrid is not "ON". This is expected and normal behavior.

Turning power OFF

Make sure that the box to the right of the OFF/ON buttons are GREEN.

To turn on the low voltage power (DVDD, AVDD and V125) and the high voltage bias click the OFF button next to the hybrid you want to power.

Note: there is often a very significant delay before the GUI updates after a change so be patient.

You should see all low voltage currents and high voltage bias ramping down.

One special feature is that the DVDD power is coupled between two hybrids (0&1,2&3, and so on). This means that powering down always results in powering down BOTH hybrids. This is expected and normal behavior.

Expert Only

Changing voltages

In EPICS control gui we can click the button to the right saying "Hybrid x" (x=[0,9]) and a new GUI pops up showing more options.

To set the voltage there are three columns to pay attention to:

Input V: used to change the Demand V

Demand V: voltage that will be applied whenever the PS is turned on for this channel.

Measured V: measured voltage

Only the bias voltage can be changed; the low voltages are "hard coded".

Changing the bias voltage

This should only be done by expert!

1. Open the hybrid view of the particular hybrid you want to change.

2. Identify the TOP or BOTTOM BIAS row and go to the Input V column.

3. In order to propagate a new value to the PS you need to

3.1 Highlight the number in the Input V box

3.2 Put your desired new voltage and directly hit Enter

Note. Don't touch the mouse after highlighting the numbers, this will remove your input and nothing will be changed.

3.3 You should see your number propagate to the Demand V column (this might take 1min, be patient!).

Using the serial interface

In the case where the operation of the power supplies can not be done through EPICS, each power supply can be accessed directly through a terminal.  After login into clon10 (see above), the command

 > tsconnect hpshv1

will bring up the display for the power supply powering the top SVT volume and

 > tsconnect hpshv2

will bring up the display for the power supply powering the bottom volume.  After each of the terminal interfaces come up, hitting N (next) will refresh the window. It will also allow you to navigate between screens
The following table provides a map from a power supply channel # to a physical location on the SVT:

Half_Module_Assignments-Power_Supply_Assignments.pdf