Vishay Micro-Measurements
System 7000 Programmer’s Reference Manual
Page 28 of 142
Trip Scan
A trip scan is the scan that satisfies a limit when no other limit is active. When a trip scan occurs
it is recorded on all channels regardless of the recording rate. Trip scans are always recorded
because they indicate which scan initiated limits-based recording. Notice how when the channel
represented as a red line crossed the threshold, it satisfied a limit but it did not cause a trip scan.
This is because limits-based recording is already active.
Figure 5 – Limit Trip Scans
Figure 5 shows 'trip scans' as yellow dots.
Defining Limits
In the System 7000 scanner defining limits is a four-step process. First define the limit conditions, next
define how you want the card to respond to a limits condition, then assign a limit condition to a channel,
and, lastly, configure how you want recording to occur based on that limit.
Defining Limit Conditions
The first step is defining a limit conditions table that is sent to each card in the system. The table
can hold up to 50 defined conditions. (Though only incremental limits type use more than 1
condition.) The following parameters are used to define this limit condition table.
Index
Index of a limit condition in the limit condition table
Test Condition
The test condition defines the test that will activate a limit.
None - This condition does not have a limit assigned.
Greater Than - Trip when the input reading is greater than the upper limit value.
Less Than - Trip when the input reading is less than the lower limit value.
Equal - Trip when the input reading is equal to the upper limit value.
Between - Trip when the input reading is between the two limit values specified.
Outside - Trip when the input reading is outside the range specified by the two limit
values.
Range -This condition is valid only when the Limits Type is set to Range mode. The
limit will be tripped when the input reading is within the specified range as defined
by the increment/decrement values.
Lower Limit
The lower limit value is used in checking the test condition. The lower limit is used by the
Less Than, Between, Outside, and Range conditions. This value is entered in analog-to-
digital converter counts.
