Ametek Sorensen Asterion DC Series, Operation Manual

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Calibration Asterion DC Series
3-54
3.6
Remote Power Programming
Remote power programming is summed with the front panel or digital setting; see
Section 3.3. Remote power programming configuration is used for applications that
require the output voltage be programmed (controlled) from a remote instrument. An
external resistance or external voltage source or 4-20mA source may be used as a
programming device. When using remote voltage programming, a shielded, twisted-
pair cable is recommended to prevent noise interference to programming signals.
3.6.1 Remote Power Programming by Resistance
Analog Reference source is selected as Resistance from the front Panel. Refer to
Figure 3-107. The resistance-programming default coefficient for output power is
(100% rated output
power) / 5 kΩ, with input at Pin 34 (PPRG_ISOUR) and return to
Pin 18 (RTN_PRG). An internal current source, factory-set at 1 mA, from Pin 20 is
utilized to drive the resistance. This produces a transfer function for output power, as
follows:
P
out
= * 1 % rated output power / 5 kΩ , with in kΩ.
Full Scale power programming resistance can be modified from default 5
kΩ to any
other value, from 2
kΩ to 10 kΩ. Refer to Section 3.1.8.4. Then the transfer function
for output power, as follows:
P
out
= * 1 % rated output power / FSC kΩ , with in kΩ.
An open circuit between remote programming pins while in remote programming
mode will output the full rated unit value. A short must be placed between remote
programming pins to output a value of zero.
Figure 3-107. Remote Power Programming Using Resistance
0 2k ohm
to
0 10k ohm
1 15
16
44 31
30
34
18
PROG_ISOUR