Laurel Electronics LAUREATE SERIES COUNTER_TIMER - Manual (Page 26)

11.3 MODES OF OPERATION
Internal Clk
Gate
Arm Signal
Input
The measurement starts with an input signal transition in one direction and ends, after the
expiration of the selected gate time, with the next input signal transition in the same direction
such that the conversion time or period is measured over an integral number of input cycles.
The internal Start signal ARMS the gate circuit so that the next input signal transition actually
OPENS the gate. When the gate is detected to be open, the gate time begins. At the end of
the gate time, the gate circuit is DISARMED, and the next input signal transition CLOSES the
gate. When both inputs A & B are active with separate gates, such as measuring Rate on both
channels, the gate time begins when both gates are detected to be open. The program
calculations begin when both gates are detected to be closed.
11.4 RATE
A ONLY, RATE A B Either one or two channels of rate may be displayed. If one channel
is displayed the input is on channel A and decimal point1, scale1 and offset1 apply to
the input. If two channels are displayed decimal point1, scale1 and offset1 apply to
channel A and decimal point2, scale2 and offset2 apply channel B. Either channel may
be displayed by pressing and releasing the reset key . Gate time setting selects the
update rate of meter. The longer the gate time, the more cycles of the input signal
averaged. If the period of the input signal is longer than the gate time, only 1 period of
the input is calculated and determines the conversion time. Time out is the length of time
the meter waits for a signal to start a conversion or end a conversion. If pulses are not
received before the time out ends, the meter reads zero. The longer the time out, the
lower the minimum frequency the meter can display
Frequency displayed in Hz with scale factor of 1 and multiplier of 1. Increasing the
multiplier increases resolution (.1 to .00001Hz). Decreasing the multiplier allows display
in kHz or MHz.
Rate displayed in engineering units by scale factor and multiplier. Using coordinates
of 2 points to scale meter, low input and high input are entered in Hz.
BATCH displays total of channel A as item 1, grand total or number of batches as item
2 and rate as item 3. Batch requires a Batch Relay board that plugs into the Analog
Output Slot. It contains Relay #3 for use as the Batch Controller. This leaves Relay #1
and Relay #2 for use as either Pre-warn, End-of-process or Rate alarms. When Reset
in the BATCH mode, the counter resets and then displays "rEAdy". It waits until the
Reset button is pushed and then immediately energizes Relay #3 and starts displaying
the Batch Total. When the preset value is reached, Relay #3 de-energizes for a period
of time equal to the GATETIME setting. At the end of GATETIME, the Batch Total resets,
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