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

_images/connector-db25.svg

Fig. 7.1 External User I/O D-Sub 25-pin Connector and Pin Layout

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 (High Speed)

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 Input

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 DBx Module has four analog inputs 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 (Pins 5, 6, 17, 18) can be configured to select different trip or set point values. For the inputs to take effect, Analog Input must be selected in the Set Point Source menu. By factory default, the analog input is disabled. If the source is selected, and one leaves the pin floating, the signal is pulled down resulting in a zero set point.

Standard analog inputs (Pins 5, 17, 18) are used for applications requiring high stability. Inputs are sampled and digitally filtered heavily to remove measurement noise and produce a stable input signals. High-speed analog input (Pin 6) is used for applications requiring fast changes. Here, the input is not filtered and updates every 500 μs.

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

Parameter

Description

Input Reference Voltage Range

Corresponding Output Range

Default Pin

Vset

Voltage Set Point

0-10V

0-100% of maximum rated voltage

None

Iset

Current Set Point

0-10V

0-100% of maximum rated current

Pin 5

Pset

Power Set Point

0-10V

0-100% of maximum rated power

None

OVT

Voltage Trip Point Setting

0-10V

10%-110% of maximum rated voltage

None

OCT

Current Trip Point Setting

0-10V

10%-110% of maximum rated current

None

OPT

Power Trip Point Setting

0-10V

10%-110% of maximum rated power

None

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 DBx Module Add-On’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 DBx Module Add-On 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 DBx Module Add-On’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.

7.2. Analog Outputs

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

Parameter

Description

Output Reference Voltage Range

Corresponding Output Range

Default Pin

Vin

Measured Input Voltage

0-10V

0-100% of maximum voltage

Pin 4

Iin

Measured Input Current

0-10V

0-100% of maximum current

Pin 3

Pin

Measured Input Power

0-10V

0-100% of maximum power

None

Rin

Resistance Set Point

0-10V

100%-0 of maximum resistance

None

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 DBx Module 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 digital input parameters:

Command/Function

Description

Default Pin

Logic

Input Enable

1-pin alternative to the Start-Stop commands.

Pin 11

Active When Present

Interlock

Normal operation requires a +5V assertion signal.

None

Normally Closed

Clear

Removes fault status if the fault is no longer present.

None

Active When Present

Lock

Block inputs from front panel keypresses.

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 3 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 DBx Module 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 their pin assignments. The pin assignment can be modified from the front panel.

The digital outputs are used to monitor the DBx Module Add-On’s internal states. A pin will output +5V when a state is active and 0V when a state is inactive. The maximum output current per pin is 20mA.

Caution

Trying to draw more than 32 mA from a digital output will damage the DBx Module Add-On’s controller.

The following table provides the selection of the available digital output parameters:

State

Description

Default Assignment

Enabled

The input is engaged and the DBx Module Add-On is processing power

Pin 7

Standby/Fault

The DBx Module Add-On is either in a standby or faulted state

None

Standby

The DBx Module Add-On is in standby

Pin 8

Fault

The DBx Module Add-On is in a faulted state

Pin 9

CV Regulation

The DBx Module Add-On is regulating voltage

None

CC Regulation

The DBx Module Add-On is regulating current

None

CP Regulation

The DBx Module Add-On is regulating power

None

CR Regulation

The DBx Module Add-On is regulating resistance

None

Lock

The lock function is active and the DBx Module Add-On is locked

None