GSE 60 SERIES Technical Reference Manual page 468

12-22 Chapter 12
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specifying that the output is normally at a high state, sinking to ground to provide the output pulse.
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to three decimal places in units of milli-seconds. This parameter does not take effect until a value for P51 is
subsequently entered. The displayed value reflects the value in effect at any given time, even if a new value has
been entered and is pending taking effect when P51 is entered. Note that the channel number referenced is that of
the channel set for the "DlyOt' function. For example if channel 5 is DlyIn and channel 6 & 7 are set for 'DlyOt',
then the first pulse width and delay time would be referenced as P50.6 and P51.6 while the second DlyOt would be
P50.7 and P51.7.
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shown to three decimal places in units of milli-seconds. When a value for this parameter is entered, the most
recent entered value for P50 also takes effect. The maximum delay time which may be specified is dependent
upon the clock selected, as shown in the table above.
GSE Scale Systems
Delay Amounts
Maximum Delay or 1000 ms
Pulse Width
The general restrictions listed Table 12-8 can be attributed to the fact that
the maximum times for the delay and the pulse width are 65,535 periods of
the selected clock.
P862: "PTyp": This parameter has a permanent selection of 'Sink'
The 'weigh mode' parameters available for this function are:
P50: Used to specify the pulse width of the output signal. It is shown
P51: Used to specify the delay amount for the output signal. It is
If a time longer than that shown for the selected clock is specified, the
maximum allowed time is implemented. If a negative time is specified,
a time of zero is implemented. The minimum response time for the
delay output is around 8 µs (0.008 ms).
'D O ' D
LY T ETAILED
When an input signal edge is detected an event is scheduled, based upon
the value of P50, using the specified internal clock. This event causes the
output signal to change state. When that state change occurs another
event is scheduled, based upon P51, which then causes the signal to
revert back to its original state.
D F A
ELAY UNCTION
The delay in/out function pair can be used for various applications, most
notably the triggering of SCRs for vibration control of vibratory feeders.
Vibratory feeders are typically supplied with an AC half wave rectified
signal which is supplied by an SCR that fires some variable time after the
zero cross of the AC waveform.
A TTL signal must be generated which indicates the zero cross of the AC
power source. That signal must be connected to the DlyIn input.
The 'DlyOt' signal may then be connected to a circuit which is used to fire
an SCR at the desired phase point of the AC waveform. A 0° (0 ms delay)
SCR firing results in maximum vibration while a 180° (8.33 ms @ 60 Hz)
firing produces no vibration. Thus varying the delay time between 0 and
8.33 ms provides an adjustable vibratory control.
Appropriate isolation techniques must be implemented to prevent damage
to the 660 electronics and to reduce the risk of electrical shock.
125 ms
O
PERATION
PPLICATIONS