Instrument Definition - HP E1328A User Manual

Instrument Definition

12 Getting Started with the HP E1328A
In the calibrated mode, output accuracy is dependent on the date of the last
electronic adjustment performed (see Appendix A). This accuracy is
maintained by use of stored adjustment constants in memory. Each channel
has independent adjustment constants for both voltage and current, which
are updated by performing the appropriate electronic adjustment procedure
(see Chapter 3).
The electronic adjustment procedures used to update the channel's stored
voltage and/or current adjustment constant in memory requires only a
⁄
multimeter (5 1 -digit, 0.015% of reading + 1 mV accuracy) to complete. If
2
a system multimeter is used, the electronic adjustment procedures can also
be automated.
The four channels are electrically isolated from each other, and from chassis
ground. This allows the usable output range (voltage and/or current) to be
expanded by linking multiple channels. For example, the output voltage range
can be expanded to 48 Vdc by linking channels in series, and the output current
range can be expanded to 96 mAdc by linking channels in parallel.
Both voltage and current outputs on all channels are provided with output
short circuit protection. Additionally, each channel configured for
outputting voltage has no-fault remote-sensing capability to ensure accurate
voltages at the load. If one of the sense leads become disconnected, the
D/A Converter will automatically revert to local sensing.
The AC FAIL line (from the mainframe) is constantly monitored by the
D/A Converter. If power fails, the D/A Converter channels are shut down
to conserve power and provide greater hold-up time for the mainframe
power supplies.
HP plug-in modules installed in an HP mainframe are treated as
independent instruments, each having a unique secondary HP-IB address.
Each instrument is also assigned a dedicated error queue, input and output
buffers, status registers and, if applicable, dedicated mainframe memory
space for readings or data. An instrument may be composed of a single
plug-in module (such as a counter) or multiple plug-in modules (for a
switchbox or scanning voltmeter instrument).
Chapter 1