Daniel gave me the test rig for the AM stabilized EOM drivers that we should be receiving from Caltech this week. This allowed me to test that the Beckhoff controls and readbacks work as expected. I also made a summary screen (ISC_CUST_EOMDRIVER.adl) of these readbacks and controls, which is accessible from the LSC dropdown menu on the sitemap.
The chassis is labeled "Corner 6", and has 2 unconnected connectors labeled "EOM Driver A" and EOM Driver B".
The "A" connector controls the 45 MHz channels, and the "B" connector controls the 9 MHz channels.
The controls and readbacks performed the same for both channels, so I'll only write out the list once.
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"Power ok" readback works
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"Excitation enable" switch functions, although the LED on the test rig seems backwards (I don't know if the test rig is wired backwards, or if the EPICS controls are backwards).
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When the EPICS switch says "off", the LED is on.
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When the EPICS switch says "on", the LED is off.
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"Excitation switch" readback works
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"Remote control" readback works
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"RF on" readback works
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"RF control" readback works
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The readback reports directly the number of Volts.
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The 45 MHz channel reads high by less than 1% (ex. 6 V input with voltage calibrator read back as 6.04 V)
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The 9 MHz channel reads low by less than 1% (ex. 6 V input with voltage calibrator read back as 5.99 V)
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"RF set mon" readback works
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Table of selected values:
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Voltage input with voltage calibrator |
RF Set Mon readback value |
0.1 V |
-13 |
1 V |
7 |
3 V |
16.6 |
5 V |
21.0 |
7 V |
24.0 |
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"RF set" input works
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Minimum acceptable slider value is 4.0. This corresponds to the word 00101000 (LEDs for 32 and 16 on, all others off).
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Each slider value increment of +0.1 adds 1 (in binary) to the word.
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Slider value 25.5 corresponds to the word 11111111 (all LEDs on)
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Slider value 25.6 corresponds to the word 00000000 (all LEDs off)
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Values larger than 25.6 continue counting up by 1 bit per 0.1 increment
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Largest acceptable slider value is 27.0, which corresponds to 00001110 (LEDs for 8, 4, 2 on, all others off)
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"RF out" readback works
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Table of values is identical to the RF Set Mon.
I need to investigate the situation with the "Excitation Enable" switch, but other than that we should be ready to go when the EOM driver arrives, if we decide to install it.
The RF setpoint goes from 4dBm (lowest setting) to 27dBm (highest setting) in steps of 0.2dB. The binary should start at zero for the lowest setting and increase by 1 for each step. This is a PLC problem.