American Magnetics 4Q06125PS-430 High Stability Integrated Power Supply System - Manual (Page 34)

16 Rev. 3
Installation
Magnets w/o Persistent Switch
Aux connector J2 on the rear panel of the Model 13x Liquid Helium
Level Instrument (12). Refer to section A.6.2 on page 151.
i. Connect each device line cord from the respective device to the
appropriate power receptacle.
j. Remote communications via Ethernet and/or RS-232 can be
accomplished by connecting suitable cabling to the Model 430
Programmer rear panel ETHERNET and/or RS-232 connectors.
2.6 Special Configurations
The Model 430 Programmer has been designed for optimal operation with
a superconducting magnet (i.e. a very low resistance, high inductance
load) with a persistent switch. The Model 430 Programmer is capable of
controlling current to other loads; however, some modification to the
Model 430 Programmer settings and/or connections must usually be made.
Two commonly encountered configurations are: 1) superconducting
magnets without a persistent switch, and 2) operation on a short-circuit or
low resistance load.
2.7 Superconducting Magnets with No Persistent Switch
An external stabilizing resistor for superconducting magnets without a
persistent switch is no longer required 1 . However, these systems do
require a specific Model 430 Programmer stability setting based on the
magnet inductance as follows:
For magnet inductance <= 100 Henries (H):
Stability Setting = (100 - H)
For magnet inductance > 100 Henries:
Stability Setting = 0
2.8 Short-Circuit or Resistive Load
If operating with a short-circuit as a load without the presence of a
superconducting magnet, the Model 430 Programmer must be manually
configured for stability. Normally, when the persistent switch heater is
deactivated, the Model 430 Programmer sees essentially a short-circuit
load since the persistent switch shunts all current flow away from any
connected magnet. Therefore, one method of operating a short-circuit is to
1. Effective with Model 430 firmware version 1.62.