PMT-200 (sometimes also referred as TGPMT ) card is part of the Tiger Controller that lets user power and interface with two Photo Multiplier Tube (PMT).
Note: Contact ASI if your preferred PMT isn't shown above. We will be happy to look into it.
A Photo Multiplier tube(PMT) is a very sensitive instrument. Great care must be taken when handling and using it. Please read the PMT manufacture's notes on Safety precautions and Handling instructions before using the PMT. Below are excerpts from Hamamatsu's PMT catalog.
Some PMT modules like H10722 operate with +/- 5Volts, and others like H9306 operate with +/- 15Volts. PMT-200 is compatible with both PMTs, however it needs to be configured with Jumper to provide the necessary voltage to the PMTs.
Note the configuration is card wide and applies to both channels. Two PMTs with different input voltages cannot be used with the PMT-200 card at the same time.
This Configuration is for H10722 , H10723, H11462 and other PMT series.
The Blue Jumpers stay the same between configurations . The Pink Jumpers apply to +/- 5 Volt configuration. They are
This configuration is for H5784, H7827 , H10492 , H10493 and others PMT series.
Not always true, if the PMT has a 7-pin HiRose connector its more likely a H5784 PMT
The Blue Jumpers stay the same between configurations . The Red Jumpers apply to +/- 15 Volt configuration. They are
PMT-200 connects to the PMT tubes thru a RJ45 Ethernet cable in EIA-568B configuration. This is common cable used in IT/networking. If your cable is malfunctioning or misplaced, in a pinch a common ethernet cable could be used instead. If in doubt contact ASI for a replacement.
The connector on the PMT and PMT-200 are NOT ethernet connector. They are wired in a different manner. Connecting anything other than a PMT to the PMT-200, or vice-versa will cause damage and failure.
|1||V+ to PMT (+5V or +15V)|
|3||V- to PMT (-5V or -15V)|
|4||Gain set voltage to PMT (upto 1V)|
|6||VREF from PMT (+1.2V)|
|7||Signal from PMT|
The PMT-200 has an electronics mechanism where if the PMT output signal reaches 80% of the maximum output voltage, it shuts off the PMT by setting the Gain control voltage to 0 Volts. This mechanism helps protect the PMT from excessive light which deteriorates the photocathode's sensitivity.
PMT-200 indicates the overload state with the Faceplate LED going from Green to red, and the [addr#]LOCK X? Y? queries return a 0.
The PMT-200 can be controlled manually or thru serial command.
PMT gain can be set manually by adjusting the Dial or with WRDAC command. There is no switch to pick your prefered control method , instead a OR function is used. So if you prefer serial command control to set gain , make sure Dial is set to 0. Vice-Versa , if you prefer dial to control the gain , set [addr#]WRDAC X=0 Y=0.
The dial or the command adjust a control voltage to the PMT. This changes the high voltage applied to the Photomultiplier tube that changes the ratio of anode output current to cathode output current ie Gain.
Note: Over stimulating the PMT with high gain over extended period of time will lead to decrease in PMT's sensitivity.
When PMT overloads , it can recovered manually by pressing the Overload Reset button or by issuing the LOCK X Y reset command.
The PMTs signal can be read as a 0-4V analog signal or can be queried with a RDADC serial command which reads it from an ADC on board the PMT card.
The PMT signal out of the PMT-200 has a 50ohm output impedance. When driving a load with 50ohm input impedance , expect ×½ gain.
Serial commands which control function on PMT-200:
PMT-200 is supported by MicroManager 1.4.23 and above . It can be found as part of the ASITiger Device Plugin , and is classed as a SignalIO device.
Each PMT-200 card supports upto two PMTs, MicroManager automatically detects this and defines them as two separate SignalIO devices.
Below is a brief description of the device functions and properties,
GetLimits(double& minVolts, double& maxVolts) , Use to query the device for maximum and minimum values that can be returned.
SetSignal(double volts), Not relevent for a PMT , hence not implemented.
GetGateOpen(bool& open), when a PMT is exposed to excessive light , PMT-200 triggers an overload state which shuts the PMT off. More info on Overload is here. This function can be used to query the PMTs current state. Returns True when PMT is enabled or working. False when PMT is overloaded and disabled. Same function as LOCK serial command.
SetGateOpen(bool open) , this function can be used to try reset the PMTs overload state. True attempts to Reset the overload state. False performs no action. Same function as LOCK serial command. More info Overload state reset is here
ADC Averaging Size, View and set the PMT-200 ADC Simple Moving Average routine's sample size. Same function as ERROR serial command. Refer to ADC spec for more info. This is a card wise settings , so changing this property for one PMT will also change it for another PMT that shares the same card.
PMT Signal, a read only property that shows the ADC reading of the PMT. Same function as RDADC serial command.
PMT Overload Reset, a write only property that lets the user try reset the PMT's overload state. Possible states are OFF (default) , ON which immediately applies the Reset pulse, and then changes to RESET applied state. More info on Overload state reset is here
SaveCardSettings, a write only property , which lets the user save the current settings into the PMT-200 cards's memory , or restore everything to factory defaults.