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Panel Indicators and Connectors – Rear Panel
60
Normally, the DC power is connected before the
Power
switch is turned ON. However, no damage will occur
if this switch is already in the ON position when the DC power is connected, or when the AC power input is
connected to the external power supply.
Chassis Ground
The rear panel
Chassis Ground
is intended for one use only. When the Reference 3000 is used with cells
isolated from earth ground, connecting the
Chassis Ground
to earth ground may lower the noise measured in
the system. Note that the chassis of the Reference 3000 is connected to Floating Ground. See Chapter 1 for
safety information concerning this connection.
Either a banana plug or the stripped end of a wire can be connected to the
Chassis Ground
binding post. The
other end of the wire is then connected to earth ground.
A black banana-plug-to-banana-plug lead is provided with your Reference 3000. You may find it useful when
making this earth-ground connection.
USB Port
The
USB
port on the rear panel of the Reference 3000 is a Type B connector as defined in Revision 1.1 and
2.0 of the USB Specification. Use a standard, shielded, Type A/B cable to connect this port to a computer’s
USB port or a USB hub (preferably an externally powered hub). The two ends of a Type A/B cable are
different: the more-rectangular end plugs into the computer, and the more-square end plugs into the
Reference 3000.
A suitable USB cable was included with your Reference 3000 shipment. If this cable is lost, replace it with a
cable from your local computer retailer.
The Reference 3000 is a High Speed USB 2.0 peripheral, capable of data-transfer at 480 Mbits/second. If it is
plugged into a computer port incapable of High Speed operation it will downgrade to USB 1.1 full-speed
operation (12 Mbits/second). Obviously, data-transfer speed will be slower if this occurs.
USB
port
Thermocouple
input
Misc I/O
connector