Specifications
OWNER’S GUIDE SIGNAL CONNECTIONS | 8165
Two examples of lter settings:
The 100 ns lter will pass all pulse widths (high and low) that are 100 ns or longer. It will block all pulse
widths that are 75 ns or shorter. The 5 μs lter will pass all pulse widths (high and low) that are 5 μs or lon-
ger and will block all pulse widths that are 4.975 μs or shorter.
The internal sampling clock (time base) is 80 MHz, so the period time amounts 12.5 ns. Pulse widths be-
tween gate time minus two internal time base period times may or may not pass, depending on the phase of
the input signal with respect to the internal time base.
Properties of all lter settings:
Reset on start measure
Usually all counters are reset at the start of data acquisition, i.e., the counter value is set to zero at the start
of data acquisition. In some applications this is not required. For example, an angle encoder is adjusted
to the physical zero position at the beginning of a test procedure. By resetting the counter at every start of
the measurement this adjustment will be lost. Without this reset the counter is also active if the acquisition
is interrupted between the test cycles. As a result the counter types out the absolute angle position at the
measurement output all the time.
Count Direction
As default setting the count direction is in up-counting mode. Every rising edge at the input will increase the
counter value. The DEWE-ORION-1616-10x supports also down counting without the need of an additional
input like in the up/down counting mode.
No new value available
Especially in every kind of input period time measurement mode (also pulse width or two pulse edge separa-
tion measurement) there may be new information between two samples. Also measuring the line frequency
of about 50 Hz with a sample rate of 10 kSamples/sec means, that only after every 200th measurement
new input frequency information is available. Another example is the measurement on rotating machines if
the sensor output frequency is lower than the sample rate. Depending on the application you can choose
between two different output data settings:
Repeat last value: last measured cycle time is taken until a new measured cycle time is available
Make zero value: as soon as no input information is available the output is set to zero