Valhalla Scientific 4300C, Руководство по эксплуатации

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TC Mode Key and Sensor Receptacle
This portion of the front panel is utilized only during
temperature compensated type measurements (TCM). TCM
mode is described in detail in the next section.
Critical to this measurement mode is precise temperature
sensing, which entails solid and reliable connections between
the sensing device and the instrument. The temperature sensor
receptacle is designed so that the mating connector/sensor, the
Valhalla Scientific Omni Compensator
5 , can be inserted only in the proper mating position. A red dot on
the Omni Compensator and a red tab on the receptacle are met to guide you in the insertion of the
connector in the receptacle.
The TCM feature of the 4300C, arithmetically calculates the resistance value to display utilizing the
ambient temperature and other parameters that will be present later. It is solemn for the user to be aware
if the TCM mode is enabled or disabled so that the display reading may be interpreted correctly.
The green LED located within the TCM key is the visual indication that the TCM mode is on. A “Fault”
message on the display indicates a missing sensor or that the sensor is not properly inserted in the
receptacle.
The TCM key is used to enable or disable the TCM mode.
HLC LEDs
This portion of the front panel is designated to give the user a visual
indication of the HLC results. HLC mode is described in detail in the
next section. The HLC LEDs are active only when the Hi-Lo comparator
mode (HLC) is in use. The green LED, labeled “GO”, is on if the
measured resistance value is between the limits
6 set by the user. The
yellow LED, labeled “LO”, is on if the measured resistance value is less than the lower limit. The red LED,
labeled “HI”, is on if the measured resistance value is greater than the upper limit.
Cable Disconnect Status Indicators
The SAFE and UNSAFE LEDs indicate whether it is safe to disconnect
the test leads from the load or from the instrument. When a highly
inductive load is being measured, a potentially lethal back-EMF is
induced when the test current is removed. The 4300C provides a
discharge path for this back-EMF and monitors the voltage. The SAFE
LED is illuminated when the back-EMF is less than five volts.
5 The Omni Compensator is an optional accessory to the 4300C. See Measurement Modes and Functions for more
detail.
6
See Page 30 for detail on how to set the Hi-Lo limits.