AMETEK SGA Series - Manual (Page 68)

Operation Sorensen SGA Series
3-18 M550129-01 Rev AG
3.5
REMOTE CURRENT PROGRAMMING
Remote current programming is used for applications that require the output
current to be programmed (controlled) from a remote instrument. An external
resistance or external voltage source may be used as a programming device.
When using remote current programming, a shielded, twisted-pair cable is
recommended to prevent noise interference to programming signals.
3.5.1 REMOTE CURRENT PROGRAMMING BY RESISTANCE
The resistance-programming coefficient for output current is
(100% rated output current) /
5 kΩ, with input at Pin J1-22 (IP RES) and
return to Pin J1-23 (IP RTN). An internal current source, factory-set at 1 mA,
from Pin J1-22 (IP RES) is utilized to drive the resistance. This produces a
transfer function for output current, as follows:
Iout = R * (100% rated output current) / 5 kΩ), with R in ohms.
If multiple switches or relays are used to select resistors to program different
current levels, make-before-break contacts are recommended.
Note:
If an external resistance is used for remote programming, the current
programming return Pin J1-23 (IP RTN), must be connected directly to, or
within ±3 V, of the circuit common, Pins J-6 and J1-24. See Figure 3-13 for
connection requirements.
Figure 3-13. Remote Current Programming Using Resistance