Waygate Technologies Krautkramer USM 10, Руководство по эксплуатации

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5 Operation Pulser Receiver
120 Rev. - (09/2021) Krautkrämer USM 100
Pulse Width
You can use this function to adjust the pulse width for
the square-wave pulser. You can adjust a value within
the range of 40 … 500 ns (nanoseconds) in steps of
10 ns.
The following equation produces an approximation for
the suitable pulse width:
Nominal width in nanoseconds
= 500/probe frequency in MHz
For example, the equation for a 2.25 MHz probe results
in:
Nominal width in nanoseconds
= 500/2.25 ns = 222 nanoseconds
Note
The values of Voltage and Pulse Width can
be automatically limited, depending on the
PRF (pulse repetition frequency). This func-
tion is used for limiting the signal loss.
PRF Mode
You can choose between the Auto and the Manual
mode for the PRF (pulse repetition frequency) setting.
When you select Auto the function PRF Value is
locked. The PRF is set automatically to a value of 50%
of the maximum possible PRF.
Select Manual to set the PRF Value .
PRF Value
The pulse repetition frequency indicates the number of
times an initial pulse is triggered per second.
The larger your test object, the smaller PRF values are
needed to avoid phantom echoes. However, the A-scan
update rate becomes lower in the case of smaller PRF
values. High values are therefore required if a test ob-
ject should be scanned fast.
The best way to determine the suitable PRF value is by
experimenting: Start from the highest value and reduce
the value until there are no more phantom echoes.