HP 6826A Service Manual

CAUTION
Observe polarity when connecting sense leads
to the load.
3-39 For reasonable load lead lengths, remote sensing
limits degradation of the performance of the supply. How¬
ever, if the load is located a considerable distance from the
supply, added precautions must be observed to obtain satis¬
factory operation. Notice that the voltage drop in the load
leads subtracts directly from the available output voltage.
Because of this, it is recommended that the drop in each
load lead not exceed 1.0 volt, if a larger drop must be toler¬
ated, please consult an HP Sales Engineer.
NOTE
Due to the voltage drop in the load leads, it may
be necessary to readjust the constant current
crossover limit setting in the remote sensing
mode.
3-40 REMOTE PROGRAMMING
---CAUTION--—
External programming resistors must be connec¬
ted to the appropriate rear terminals before
power is applied to the instrument
3-41 The constant voltage and constant current outputs
of the BPS/A can be programmed {controlled) from a re¬
motely located device such as HP 6940A Multiprogrammer
or HP 6941A Multiprogrammer Extenders. Either a resis¬
tance or voltage source can be used as the programming de¬
vice. The wires connecting the programming terminals on
the rear of the BPS/A to the remote programming device
should be twisted or shielded to reduce noise pickup,
3-42 Resistance Programming Constant Voltage. A
programming resistor (Rpy), connected as shown in Figure
3-6, can be used to control the voltage output or gain pro¬
vided that the MODE switch is in the POWER SUPPLY or
the VARIABLE GAIN AMP position. Resistance program¬
ming of the constant voltage output is not applicable in the
FXD GAIN AMP mode of operation. The VOLTAGE con¬
trol on the front panel is disconnected (disabled) for the
strapping connections shown in Figure 3-6. To maintain the
stability and temperature coefficient of the instrument, use
programming resistors that have stable low noise and low
temperature characteristics {less than 20 ppm/°C.). Also,
they should operate at less than 1/30th of their wattage rat¬
ing to minimize short term temperature effects.
X MUST BE ISOLATED FROM CONTROL GROUND
Figure 3-6. Remote Resistance Programming,
Constant Voltage/Constant Current
3-43 Power Supply. For power supply operation, the
bipolar output voltage varies linearly from a maximum neg¬
ative value through zero to a maximum positive value accord
ing to the value of the programming resistance Rpv- The
voltage output ranges and corresponding values of Rpy
are as follows:
3-6

HP 6826A Specifications

General

Brand	HP
Model	6826A
Category	Power Supply
Language	English