Valhalla Scientific 4300C, Руководство по эксплуатации

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“HLC” – Hi-Lo Comparator Mode
Another useful feature of the 4300C is the Dual Limit
Comparator (HLC). This feature helps eliminate operator
interpretation of ohmmeter readings. Operator error and
fatigue are drastically reduced while significantly increasing
testing efficiency.
A common application is receiving inspection of precision resistors by unskilled operators using the HLC
mode. If, for example, the resistors to be inspected and tested are 1 KΩ ± 0.1%, the 4300C would be set
on the 2kΩ range; the upper limit would be set at 1.0010kΩ, and the lower limit to 0.9990kΩ. If measured
resistance is within these limits, the GREEN indicator will remain illuminated, indicating a within tolerance
condition. If either RED or the YELLOW indicator is illuminated, that respective limit has been exceeded
and the test sample should be rejected.
HLC Relay Terminal
The 4300C provides relay closure outputs which can be used to implement an automated batch sorting
system for components or products, operate counters, sound alarms, or shut off a process. Resistors,
transformers, strain gauges, thermocouples and thermistors
are a few items which could be individually toleranced in this
manner for matching purposes.
The HLC relay terminal is internally wired to three relays which
are active only when the HLC mode is selected. According to
the result of the comparison, one of the relays will have its
contacts closed while the remaining two relays will have
contacts open. The standard "relay contact closure" feature
allows an automated sorting process to be set up at an
economical cost. The screw type terminal allows connections to wire or spade lugs. Contacts are rated at
100V, 100mA. The table below is a truth table of the contacts. Ω’s symbol represents the load measured
value; UL is the upper limit and LL is the lower limit set by the user.
HLC State HLC Result XLO GO XHI
ON LL≤Ω≤UL OPEN CLOSED OPEN
ON Ω<LL CLOSED OPEN OPEN
ON UL<Ω OPEN OPEN CLOSED
OFF X OPEN OPEN OPEN
OFF X OPEN OPEN OPEN
OFF X OPEN OPEN OPEN