Valhalla 2300, Operation Manual

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available over the bus; no SRQ's and a
C
R
L
F
at
the end of the transmitted data.
7-7-9. Average Power and Watt-Hour
Commands
These commands are used to control the
compiling of average power and watt-hours.
The "S" command starts compiling while the
"F" command stops compilation and
calculates average power or watt-hours
accumulated since the receipt of "S". The
calculation of either average power or watt-
hours is determined by the "T" command (7-
7-5) current at the time "F" was received. "F"
commands received before "S" commands are
ignored.
Sample Program #1 (Average Watts):
10OUTPUT 715;"S" start compiling data
20OUTPUT 715;"T3" use the data for avg pwr
30OUTPUT 715;"F" stop compiling & calculate
40 WAIT .5 recommended delay 500ms
50ENTER 715;A$ display the result
(A$ will contain the average power data)
Sample Program #2 (Watt-Hours):
10OUTPUT 715;"S" start compiling data
20OUTPUT 715;"T4" use the data for watt-hours
30OUTPUT 715;"F" stop compiling & calculate
40 WAIT .5 recommended delay 500ms
50ENTER 715;A$ display the result
(A$ will contain the watt-hour data)
Voltage, current and instantaneous power data
may be read while compiling power data.
Reading average power or watt-hour data
before the receipt of "F" will produce
undefined results. Changing the "W"
command following the "S" command will
also produce undefined results.
Note:The following manipulations of the
output result are required when using
these options:
Option LF: Multiply watt-hours by 2
Option HS-5: Divide watt-hours by 2
Option HS-12: Divide watt-hours by 5
7-7-10.
Reading the Displays
Upon receipt of one of the five "T" queries
(see 7-7-5), the 2300 places either the volts,
amps or watts displayed data in its output
buffer. This data may be now be read by the
system controller. The data is of the
following format:
±1.9999En,O
{D?}
Where:
±1.9999 are the significant digits of the measurement.
En is the exponent (power of 10) to be applied to the
significant digits i.e. ±1.9999 x 10
n
O indicates an overrange condition on any channel.
{D?} is the output data terminator sent to signify the end of
the data. This is usually a __, but may be
changed using the "D" command (see 7-7-
6).
The data is returned in scientific notation with
the units of watts, volts or amps depending on
which "T" query was sent. If no "T" query
was sent, the 2300 returns its default data
which is the voltage measurement.
The 2300 may be read at any time; however,
caution must be taken to avoid erroneous data.
A delay of 500ms should be allowed
following a "Tn" query before reading data.
A delay of 5 seconds should be allowed for
maximum accuracy following a range change
(In or Vn), or channel change (Wn).
The following are sample programs (in
Hewlett Packard Basic) that may be used to
read the 2300's output buffer. Assume that
the 2300 has inputs applied to it such that
VOLTS = "125.72", AMPS = "79.52" and
POWER = "9997", and that the instrument is
displaying
φ
B data.