7. Operation: External User I/O

The analog-digital inputs and outputs for the External User I/O port are reconfigurable, allowing the pins to be assigned according to the application and desired parameters. Therefore, the External User I/O pins are grouped according to function, with numerous selectable parameters in the following groupings: Analog Inputs, Analog Outputs, Digital Inputs, and Digital Outputs. Refer to each of these sections for the various parameters that can be assigned to the External User I/O pins.

Note

Not all pins need to be set

The following table provides the External User I/O pin layout:

User I/O Pin Designation Description
1 GND ANALOG Ground (Analog Reference)
2 +10V REF 10V Reference Voltage, 20 mA max
14 +5V 5V Reference Voltage, 20 mA max
25 GND Ground
5 AI0 Analog Input
6 AI1 Analog Input
17 AI2 Analog Input
18 AI3 Analog Input
3 AO0 Analog Output
4 AO1 Analog Output
15 AO2 Analog Output
16 AO3 Analog Output
11 DI0 Digital Input
12 DI1 Digital Input
23 DI2 Digital Input
24 DI3 Digital Input
7 DO0 Digital Output
8 DO1 Digital Output
9 DO2 Digital Output
10 DO3 Digital Output
19 DO4 Digital Output
20 DO5 Digital Output
21 DO6 Digital Output
22 DO7 Digital Output
13 NC No Connection

7.1. Analog Inputs

The WRx Series MagnaLOAD has four analog input signals on its rear External User I/O 25-pin port. The External User I/O pin layout is defined in Operation: External User I/O.

The four analog inputs are configurable, allowing selection of the desired input parameters. By factory default, all of the analog input signals are disabled. The following table provides the selection of the available analog input parameters:

Parameter Description Input Reference Voltage Range Corresponding Output Range
Vset Voltage Set Point 0-10V 0-100% of maximum rated voltage
Iset Current Set Point 0-10V 0-100% of maximum rated current
Pset Power Set Point 0-10V 0-100% of maximum rated power
OVT Voltage Trip Point Setting 0-10V 10%-110% of maximum rated voltage
OCT Current Trip Point Setting 0-10V 10%-110% of maximum rated current
OPT Power Trip Point Setting 0-10V 10%-110% of maximum rated power

A 0-10V input on the Voltage, Current, and Power Set Point input parameters corresponds to a proportional setting of 0-100% of product’s maximum rated voltage, current, and power, respectively. As trip point settings are available up to 110% of the MagnaLOAD‘s maximum ratings, a 10V input on these trip points settings will correspond to 110% of the unit’s maximum rating.

Note

Applying the same voltage reference to a set point input and its corresponding trip point setting is a common way to minimize the number of connections necessary from controlling hardware. With the same voltage reference on the two corresponding inputs, the product will be provided with a set point and then a trip setting 10% above that value. For example, applying the same +5V reference signal for both Vset and OVT on a product rated for 500 Vdc maximum, will correspond to a Voltage Set Point of 250 Vdc and a OVT setting of 275 Vdc.

If an analog input signal is enabled on the External User I/O, a voltage reference must be provided on the selected pin for that parameter. With the input signal enabled, the MagnaLOAD will no longer reference the digitally stored values for that parameter, meaning no other programming method will be available for that parameter as long as it’s assigned to an analog input. For example, if the user enables Iset on one of the analog input signals, Iset can no longer be programmed from the front panel or computer interface; instead, the user needs to provide a 0-10 V reference on the selected pin.

The analog reference ground is provided on Pin 1 of the External User I/O. As the MagnaLOAD‘s power processing stages can develop electrical noise on the earth ground, this analog reference ground is provided as a clean reference control ground path allowing for accurate low-level voltage programming and measurement. The analog reference ground is tied to the product’s earth ground through resistance, to help filter any noise on the ground.

The set points driven by the analog inputs are visible on the front panel set point menu and can also be queried from the computer interface. Similarly, the trip point settings driven by the analog inputs are visible on the front panel trip point sub-menu and can be queried from the computer interface.

7.1.1. Analog Voltage Programming

7.1.2. Analog Current Programming

7.1.3. Analog Resistance Programming

7.2. Analog Outputs

Parameter Description Output Reference Voltage Range Corresponding Output Range
Vin Measured Input Voltage 0-6V 0-100% of maximum voltage
Iin Measured Input Current 0-6V 0-100% of maximum current
Pin Measured Input Power 0-6V 0-100% of maximum power
Rin Resistance Set Point 0-6V 100%-0 of maximum resistance

The voltage, power, and resistance measurements provided by the analog outputs are measured at the configured sense location. If remote sense is enabled, the measurement will be taken at the sense leads; otherwise, the measurement will be taken at locally at the DC input terminals.

7.3. Digital Inputs

The WRx Series MagnaLOAD has four digital input signals on its rear External User I/O. The External User I/O pin layout is defined in Operation: External User I/O.

The four digital inputs are reconfigurable, allowing the user to change the pin assignments. The pin assignment can be modified from the front panel or from the MagnaWEB software.

Each digital input function is activated using +5V logic, but the logic varies among the available functions. This logic used by each function is detailed in the table below.

The digital input impedance is 10 kΩ.

A +5V reference signal is provided on Pin 14. This reference signal may be used in conjunction with external dry contacts to trigger the digital input functions.

Note

For safety, the Stop function will always take precedence over the Start function.

The following table provides the selection of the available analog input parameters:

Command/Function Description Default Pin Logic
Input Enable 1-pin alternative to the Start-Stop commands. None Active When Present

7.3.1. Digital Input Logic Definitions

Momentary
The function is triggered by the momentary rising edge of a +5V signal. The minimum pulse duration to activate a momentary digital input function is 2 ms.
Normally Closed
When the function has been assigned to a pin, +5V must be present on the designated pin for normal operation. When the +5V is removed, the function will be triggered.
Active When Present
The function is active as long as +5V is present on the designated pin.

7.4. Digital Outputs

The WRx Series MagnaLOAD has eight digital output signals on its rear External User I/O. The External User I/O pin layout is defined in Operation: External User I/O.

The eight digital outputs are reconfigurable, allowing the user to change the pin assignments. The pin assignment can be modified from the front panel or from the MagnaWEB software.

The digital outputs are used to monitor the MagnaLOAD‘s various states.A digital output will measure +5V the corresponding state is active, and 0V when the corresponding state is inactive. The maximum output current per pin is # mA.

Caution

Trying to drawing more than 32 mA from a digital output will damage the MagnaLOAD‘s controller.

State Description Default Assignment
Enabled The input is engaged and the MagnaLOAD is processing power None
Standby/Fault The MagnaLOAD is either in a standby or faulted state None
Standby The MagnaLOAD is in standby None
Fault The MagnaLOAD is in a faulted state None
CV Regulation The MagnaLOAD is regulating voltage None
CC Regulation The MagnaLOAD is regulating current None
CP Regulation The MagnaLOAD is regulating power None
CR Regulation The MagnaLOAD is regulating resistance None
Lock The lock function is active and the MagnaLOAD is locked None
Emergency Stop Fault The MagnaLOAD has tripped with an emergency stop fault None