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Model 7708 M ultiplexer M odule Instructions for use w ith DAQ6510 077144500 / April 2018 27 Calibration procedure Before calibrating th e tem perature on the m odule, make sure that p ower has been removed from the modu…
Model 7708 Multiplexer Module Instructions for use with DAQ6510
26 077144500 / April 2018
Range
Applied DC voltage
Reading limits (1 year, 18 °C to 28 °C)
100 mV
100.0000 mV
99.9935 to 100.0065 mV
1 V
1.000000 V
0.999969 to 1.000031 V
10 V
10.00000 V
9.99970 to 10.00030 V
100 V
100.0000 V
99.9955 to 100.0045 V
1000 V
300.000 V
299.983 V to 300.017 V
Calibration
The following procedure calibrates the temperature sensors on the modules.
Do not attempt to perform this procedure unless qualified to do so. Failure to recognize and
observe normal safety precautions could result in personal injury or death.
Recommended test equipment
To calibrate the module, you need the following equipment.
▪ Digital thermometer: 18 °C to 28 °C ±0.1 °C
▪ Keithley 7797 Calibration/Extender Board
Extender board connections
The extender board is installed in the DAQ6510. The module is connected to the extender board externally to
prevent heating of the module during calibration.
To make extender board connections:
1. Remove power from the DAQ6510.
2. Install the extender board into Slot 1 of the instrument.
3. Plug the module into the P1000 connector on the rear of the 7797 Calibration/Extender Board.
Model 7708 Multiplexer Module Instructions for use with DAQ6510
077144500 / April 2018 27
Calibration procedure
Before calibrating the temperature on the module, make sure that power has been removed from the
module for at least two hours to allow module circuitry to cool down. After turning on the power
during the calibration procedure, complete the procedure as quickly as possible to minimize module
heating that could affect calibration accuracy. Initially allow the DAQ6510 to warm up for at least one
hour with the 7797 calibration card installed. If you are calibrating multiple modules sequentially, then
power off the DAQ6510, quickly unplug the previously calibrated module, and plug in the next one.
You must use remote commands to run calibration. Refer to the DAQ6510 reference manual (document
number DAQ6510-901-01) for information on setting up remote communications.
To set up calibration:
1. Turn on the DAQ6510 power.
2. To make sure that the instrument is using the SCPI command set, send:
*LANG SCPI
3. Turn power off, and turn power back on.
4. On the front panel, verify that TERMINALS is set to REAR.
To calibrate temperature:
1. Accurately measure and record the cold temperature of the module surface at the center of the module with
the digital thermometer.
2. Unlock calibration by sending:
:CALibration:PROTected:CODE "KI006510"
3. Calibrate temperature on the module with the following command, where <temp> is the cold calibration
temperature measured in step 1:
:CALibration:PROTected:CARD1:STEP0 <temp>
4. Send the following commands to save and lock out calibration:
:CALibration:PROTected:CARD1:SAVE
:CALibration:PROTected:CARD1:LOCK
Errors that can occur during calibration
If calibration errors occur, they are reported in the event log. You can review the event log from the front panel
of the instrument, by using the SCPI :SYSTem:EVENtlog:NEXT? command, or by using the TSP
eventlog.next() command.
The error that can occur on this module is "5527, Temperature Cold Cal error." If this error occurs, contact
Keithley Instruments. Refer to Factory service (on page 27).
Factory service
To return the switching module to Keithley Instruments for repair:
▪ Call the Repair Department at 1-800-833-9200 or send an email to RMAREQUEST@tektronix.com for a
Return Material Authorization (RMA) number.
▪ Carefully pack the instrument in the original packing carton.
▪ Write ATTENTION REPAIR DEPARTMENT and the RMA number on the shipping label.
28 077144500 / April 2018
Safety precautions
The following safety precautions should be observed before using this product and any associated instrumentation. Although
some instruments and accessories would normally be used with nonhazardous voltages, there are situations where hazardous
conditions may be present.
This product is intended for use by personnel who recognize shock hazards and are familiar with the safety precautions required
to avoid possible injury. Read and follow all installation, operation, and maintenance information carefully before using the
product. Refer to the user documentation for complete product specifications.
If the product is used in a manner not specified, the protection provided by the product warranty may be impaired.
The types of product users are:
Responsible body is the individual or group responsible for the use and maintenance of equipment, for ensuring that the
equipment is operated within its specifications and operating limits, and for ensuring that operators are adequately trained.
Operators use the product for its intended function. They must be trained in electrical safety procedures and proper use of the
instrument. They must be protected from electric shock and contact with hazardous live circuits.
Maintenance personnel perform routine procedures on the product to keep it operating properly, for example, setting the line
voltage or replacing consumable materials. Maintenance procedures are described in the user documentation. The procedures
explicitly state if the operator may perform them. Otherwise, they should be performed only by service personnel.
Service personnel are trained to work on live circuits, perform safe installations, and repair products. Only properly trained
service personnel may perform installation and service procedures.
Keithley products are designed for use with electrical signals that are measurement, control, and data I/O connections, with low
transient overvoltages, and must not be directly connected to mains voltage or to voltage sources with high transient
overvoltages. Measurement Category II (as referenced in IEC 60664) connections require protection for high transient
overvoltages often associated with local AC mains connections. Certain Keithley measuring instruments may be connected to
mains. These instruments will be marked as category II or higher.
Unless explicitly allowed in the specifications, operating manual, and instrument labels, do not connect any instrument to mains.
Exercise extreme caution when a shock hazard is present. Lethal voltage may be present on cable connector jacks or test
fixtures. The American National Standards Institute (ANSI) states that a shock hazard exists when voltage levels greater than
30 V RMS, 42.4 V peak, or 60 VDC are present. A good safety practice is to expect that hazardous voltage is present in any
unknown circuit before measuring.
Operators of this product must be protected from electric shock at all times. The responsible body must ensure that operators
are prevented access and/or insulated from every connection point. In some cases, connections must be exposed to potential
human contact. Product operators in these circumstances must be trained to protect themselves from the risk of electric shock. If
the circuit is capable of operating at or above 1000 V, no conductive part of the circuit may be exposed.
Do not connect switching cards directly to unlimited power circuits. They are intended to be used with impedance-limited
sources. NEVER connect switching cards directly to AC mains. When connecting sources to switching cards, install protective
devices to limit fault current and voltage to the card.
Before operating an instrument, ensure that the line cord is connected to a properly-grounded power receptacle. Inspect the
connecting cables, test leads, and jumpers for possible wear, cracks, or breaks before each use.
When installing equipment where access to the main power cord is restricted, such as rack mounting, a separate main input
power disconnect device must be provided in close proximity to the equipment and within easy reach of the operator.
For maximum safety, do not touch the product, test cables, or any other instruments while power is applied to the circuit under
test. ALWAYS remove power from the entire test system and discharge any capacitors before: connecting or disconnecting
cables or jumpers, installing or removing switching cards, or making internal changes, such as installing or removing jumpers.
Do not touch any object that could provide a current path to the common side of the circuit under test or power line (earth)
ground. Always make measurements with dry hands while standing on a dry, insulated surface capable of withstanding the
voltage being measured.