2.1. Key Features
The Universal Interface Device (UID) connects two or more Magna-Power Electronics programmable power supplies for master/slave parallel or master/slave series operation. Master/slave parallel operation allows two or more power supplies to equally share output current when connected together. Master/slave series operation allows two or more power supplies to equally share output voltage when connected together. In either operating mode, the master unit commands the slave units to the proper voltage and current, while each unit displays its own individual voltage and current.
In addition to master/slave operation, the UID can be used as an interface for connecting the power supply’s control and monitoring lines to external circuitry. The printed circuit board contains a dedicated pad area for interconnecting wires and placing components for specific user applications.
A quick summary of the UID key features:
Interface for master/slave parallel and master/slave series operation
Compatible with Magna-Power SL Series, XR Series, TS Series, MS Series, MT Series, and ML Series power supplies
Passive device; no external power required
User configurable screw terminal connector
Pad area for custom circuitry
Qty (2) 6-foot 37-conductor shielded cables included
Breakout connector with included 37-pin to 15-pin cable for BDx and DBx Module integration (UID53 only)
2.1.1. Selecting a UID
The Universal Interface Device is available in three models—UID46, UID47, and UID53—which differ in how the master power supply commands its slave units and in the available connectivity:
UID46 configures the master power supply to drive the slave units through their 0-10 V external analog references, using the master’s own monitor signals as the set point source. This method tightly matches the output sharing between units, making it the recommended choice for high current systems where current imbalance must be minimized. The only drawback of this approach is a slower transient response when the system operates in voltage mode control, as the slave control loops are cascaded from the master. In current mode control, the transient response of the UID46 is the same as that of the UID47 and UID53. High current systems typically power large inductors or superconducting magnets in current mode control, so this drawback rarely applies in the applications where the UID46 is recommended.
UID47 configures the master power supply to directly control the gate drivers of the slave units. With only a single control loop in command of all units, this method provides the fastest transient response performance. The total output current of the system is always the expected combined value; for example, a two-unit parallel system delivers twice the current programmed on the master. The division of that total between the units, however, may be unequal by up to 5% of full scale, with one unit carrying slightly more than the other. For most applications this imbalance is negligible, but for very high current systems it can become significant; for example, a 5% imbalance on a 4,000 Adc model could represent a 200 Adc difference between units.
UID53 is identical to the UID47, but adds an additional 37-pin breakout connector. Together with the included 37-pin to 15-pin interface cable, the breakout connector allows a BDx Module or DBx Module to interface with the power supply while the power supply remains part of a master/slave configuration. For more information, see BDx and DBx Module Breakout (UID53).
The following table summarizes the differences between the available models:
For detailed information about master/slave operation with each model, see General.