Basic function

The EL2502-0010 has three basic operation modes with additional selection options per channel. These are accessed via the PDO selection (see figure).

Basic function 1:
EL2502-0010 - selection of the process data via Predefined PDO Assignment

"PWM, DC":

This mode should be used if both the duty factor and the cycle duration are to be changed quickly in real-time context. In this mode a start and stop time can additionally be transferred to the terminal.

  • Duty factor specification via process data (cyclic)
  • Cycle duration specification via process data (cyclic)
  • The start and stop time can be specified via "DC start time"

"PWM, period":

This mode should be used if both the duty factor and the cycle duration are to be changed quickly in real-time context.

  • Duty factor specification via process data (cyclic)
  • Cycle duration specification via process data (cyclic)
  • The start and stop time can be specified via "DC start time"

"PWM":

This mode is to be used if the duty factor only is to be quickly changed in the real-time context.

  • Duty factor specification via process data (cyclic)
  • Cycle duration via CoE (acyclic)
  • The start and stop time can be specified via "DC start time"

The PDOs can be assigned and the second channel can be switched on at the same time by clicking on one of the options marked yellow in the following diagram, or via PDOs 0x1A02 and 0x1A03 after selecting the inputs.

Basic function 2:
EL2502-0010 - additional selection of the second channel via one of the PDOs 0x1604 to 0x1607
Basic function 3:

The temporal accuracy is impaired if the second channel is activated

If a second channel is activated by selecting one of the PDO assignments 0x1604 to 0x1607 or 0x1A02, 0x1A03, please note that the additional calculations in the microcontroller slightly impair the temporal accuracy.

Process data in PWM, DC mode

Predefined PDO Assignment 'PWM, DC' (0x1603, 0x1A00, 0x1A01)

PDO
Index (Name)

Excluded PDOs
Index (Name)

PDO Content
Index (Name)

Description

Data type

0x1A00
(PWM Inputs Channel 1)

None

0x6000:01
(Overtemperature)

This is set when the temperature of the terminal exceeds 90°C.

BOOL

0x6000:04
(Short Circuit to 24 V)

This is set in the event of output overload.

BOOL

0x6000:05
(Feedback PWM)

This bit toggles with each correct DC event.

BOOL

0x6000:06
(Err. Start Time)

The new start time that was specified is in the past.

BOOL

0x1A01
(PWM Sys Time Channel 1)

None

0x6001:11
(PWM Sys Time)

System time of the µController (jitter!)

ULINT

0x1603
(PWM Per. DC Outputs Channel 1)

0x1600
(PWM Outputs Channel 1)

0x1601
(PWM Per. Outputs Channel 1)

0x7000:01
(Activate permanent)

The PWM output takes place permanently with the specified data.

BOOL

0x7000:02
(Activate DC start time)

If the bit is set, a DC output with the values set via 0x7000:11 and 0x7000:12 is initiated with each new DC start time.
If the time is in the past, the change is made immediately and Err. Start time is set. The bit DC Immediately (0x7000:03) is always evaluated.

BOOL

0x7000:03
(DC Immediately)

1: If the bit is set, the PWM output changes immediately when the DC start time is reached, which means that output glitches may occur.

0: When the DC start time is reached, the output changes without glitches.

BOOL

0x7000:04
(ERR Ack)

Resetting of the DC error counter in CoE

BOOL

0x7000:05
(DCSyncOutCh2)

If there is no PWM output on the second channel (no PDO is assigned to the channel), it can be used for a DC‑synchronous output. With each new valid start time, the output of channel 2 is toggled with the DC event and the switching of the PWM unit.

BOOL

0x7000:11
(PWM output)

The PWM output duty cycle in %

0x7FFF = 100%
0x3FFF = 50 %
0x0000 = 0%

UINT

0x7000:12
(PWM period)

The default PWM period in µs

UINT

0x7000:13
(DC start time)

The 64-bit DC start time in ns

ULINT

The process data of other operating modes are described in chapter Process data.

Data flow

The parameters are considered in the following order:

Basic function 4:
Data flow diagram EL2502-0010

Example for DC timestamp functionality

To change the PWM cycle duration and duty factor at time T1, proceed as follows:

Once the system time reaches time T1, the "Feedback PWM" bit toggles and the next event can be activated.

Legend for the diagrams in the following examples:

CH1

EL2252 DC output Ch1 with the same time stamp as EL2502-0010

CH2

EL2502-0010 sync. output Ch2

CH3

EL2502-0010 PWM output

Example 1: Immediate = TRUE

Basic function 5:
Diagram „Immediate = TRUE”

Example 2: Immediate = FALSE

Basic function 6:
Diagram „Immediate = FALSE”

In the event of an invalid timestamp (e.g. a time in the past) the current PWM signal is switched directly to the new signal after the end of the current period, as in this example (whose parameters were transferred together with the timestamp).

Example 3: Immediate = TRUE, duty factor 0 to 100%

Basic function 7:
Diagram „Immediate = TRUE”, duty factor 0 to 100%