... | ... | @@ -100,13 +100,31 @@ blocking outputs/crate, that can be supported by the design. |
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- By adopting worst case values as an indicator of extreme use of the
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board, a limitation may need to be imposed on the number of active
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blocking outputs per crate:
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- For 250ns pulses, the limit is 12 BLO outputs per crate
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(Regardless of the number of CONV-TTL-BLO boards).
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- For 1.2us pulses, the limit is 18 BLO output channels per crate
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(Regardless of the number of CONV-TTL-BLO boards).
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- As The crate will shut off the +12V power supply at 5.5A, the +12V
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fuse can be selected at 5Amps, which will offer extra protection to
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the board.
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Denia Bouhired, 10 February 2017.
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If too many blocking outputs are in operation, and if the number of
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outputs exceeds the maximum recommended, then the fuse will blow causing
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the blocking output to fail.
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Therefore, a limit on blocking outputs/crate, must be imposed. In worst
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case scenarios, each output port requires a maximum current consumption
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I (blo-out) of 420mA for maximum repetition frequency (2MHz
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repetition).
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As a rule of thumb, the maximum number of active output ports N
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(blo-out) **per crate** is:
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N (blo-out}= I(fuse+12V)/I(blo-out) thus giving:
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N(blo-out}= 5/0.4~12
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* For 250ns pulses, the limit is 12 BLO outputs per crate (Regardless
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of the number of CONV-TTL-BLO boards).
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* For 1.2us pulses, the limit is 18 BLO output channels per crate
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(Regardless of the number of CONV-TTL-BLO
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boards).
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### ***This means that during planning and installations, it is important to not allocate any more than 12 blocking output ports per crate. As the board is fuse-protected, failing to respect this limit will not damage the board, but will cause a failure in blocking repetition and will necessitate human intervention to replace the damaged fuse.***
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Denia Bouhired, 10 March 2017.
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