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# Pre-Ionization System @ the tokamak GOLEM

## Scheme

![](PreIonization.png)

[svg source](PreIonization.svg)

## Flowchart diagram (initiation)

![](VacuumSystemOperation.png)

[svg source](VacuumSystemOperation.svg)

## Codes

### Initiation (api.py)
~~~
def start_pumping(shared_namespace, controller, forevacuum_timeout=600, forevacuum_wait=10):
    """Initiate the vacuum pumping system"""
    log.info("Please open the pressurized air tank and start old turbo-mol. pump")
    log.debug("Closing rotary pump air valve")
    controller.forevacuum_Quido_set(+2)
    sleep(5)
    log.debug("Starting rotary pump")
    controller.forevacuum_Quido_set(+1)
    sleep(5)
    log.debug("Engaging rotary pump")
    controller.forevacuum_Quido_set(+3)
    sleep(5)

    log.debug("Waiting for forevacuum to form")
    elapsed = 0
    while True:
        p_ch, p_f = controller.get_chamber_pressure(), controller.get_forevacuum_pressure()
        log.debug('Waiting for forevacuum, chamber: %.2f mPa, forevacuum: %.2f mPa' % (p_ch, p_f))
        if p_ch > p_f:
            break
        if elapsed > forevacuum_timeout:
            log.error("Forevacuum stabilization timeout (%i s) reached, stopping pumping" % forevacuum_timeout)
            stop_pumping(shared_namespace, controller)
            return
        sleep(forevacuum_wait)
        elapsed += forevacuum_wait

    log.debug("Starting both molecular pumps")
    controller.panel_Quido_set(+2)
    controller.panel_Quido_set(+5)
    sleep(10)
    log.debug("Opening ultra-vacuum valve 1")
    controller.panel_Quido_set(+1)
    log.debug("Opening ultra-vacuum valve 2")
    controller.panel_Quido_set(+4)
~~~

### Termination (api.py)
~~~
def stop_pumping(shared_namespace, controller):
    """Stop the vacuum pumping system"""
    log.debug("Closing ultra-vacuum valve II")
    controller.panel_Quido_set(-4)
    log.debug("Stopping Turbo-mol. pump II")
    controller.panel_Quido_set(-5)
    #log.info('Waiting for 15 minutes to pump forevacuum at TMP II')
    #sleep(15 * 60)
    log.debug("Closing ultra-vacuum valve I, stopping turbo-mol. pump I")
    controller.panel_Quido_set(-2)        #close Ultra-Vacuum valve
    controller.panel_Quido_set(-1)        #stop turbo-molecular pump
    sleep(2)
    log.info("Please close the pressurized air tank")
    log.debug("Disengaging rotary pump")
    controller.forevacuum_Quido_set(-3)
    sleep(5)
    log.debug("Stopping rotary pump")
    controller.forevacuum_Quido_set(-1)
    sleep(5)
    log.debug("Opening rotary pump air valve")
    controller.forevacuum_Quido_set(-2)
~~~

## Connectivity with control system

![](VacuumControlSystem.png)

[svg source](VacuumControlSystem.svg)

## Photogallery

<img src='PG/2016-03-21_10-27-32_w.jpg' width=''/><br/>Vacuum control system<br/>
<img src='PG/2016-03-21_10-30-32_w.jpg' width=''/><br/>From top to bottom: Galvanic insulation, UV valve #2, TMP #2<br/>
<img src='PG/2016-03-21_10-31-00_w.jpg' width=''/><br/>Vacuum vessel Vacuum gauge<br/>
<img src='PG/2016-03-21_10-31-43_w.jpg' width=''/><br/>Comment<br/>
<img src='PG/2016-03-21_10-32-31_w.jpg' width=''/><br/>Comment<br/>
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