Example 1: Current Consumed by a Local Configuration

Introduction

This first example is for a local configuration (controller and its local expansion modules). A later example is based on a remote configuration (TM5 Receiver module and its remote expansion modules). From these examples, you should be able to make the calculations necessary for your TM5 System.

In a local configuration, the Controller Power Distribution Module (CPDM) connects:

odirectly the external power supply to the 24 Vdc I/O power segment.

othe external power supply to the internal power supply that generates the power distributed on the TM5 power bus, which is derived from the 24 Vdc Main power connection.

All current consumption values are documented in the TM5 Consumption Table.

Planning Example

This configuration example includes:

oThe controller TM258LF42DT equipped with embedded DI12DE and DO12TE electronic modules.

oSome expansion modules:

oTM5SAI4L

oTM5SDI12D

oTM5SDI4D

oTM5SDM12DT

oTM5SDI4A

oTM5SDO4TA

oTM5SDO12T

oTM5SDO2T

oTM5SDO2R

oAssumptions used for the purposes of calculating the consumption of this example:

CPDM: The maximum current distributed on the 24 Vdc I/O power segment is limited by an external isolated power supply of 6300 mA.

DO12TE: Only 50 % of the outputs are active at any given time, and that the maximum current draw of any given output is 500 mA, or 3000 mA total for the module.

TM5SDI4D: The current to supply the electronic sensors of this example has been estimated at 50 mA per sensor, or 200 mA total for the module.

TM5SDM12DT: The sum of the current draw for all outputs connected to the module is never more than 1500 mA at any given time.

TM5SDO12T: Only 50% of the outputs are active at any given time, and that the maximum current draw of any given output is 500 mA, or 3000 mA total for the module.

TM5SDO4TA: The sum of the current draw for all outputs connected to the module is never more than 2000 mA at any given time.

TM5SSDO2T: The sum of the current draw for all outputs connected to the module is never more than 600 mA at any given time.

The following table shows the current supplied and consumed in mA on the TM5 power bus and the 24 Vdc I/O power segment:

Current Consumed on the 24 Vdc I/O Power Segment

The 24 Vdc I/O power segment begins with the embedded DI12DE electronic module and finishes with the TM5SDO2R expansion module. The capacity of this 24 Vdc I/O power segment is limited to 6300 mA in this example.

In this example, the total current consumed on the 24 Vdc I/O power segment is 10694 mA and exceeds the 6300 mA capacity of this segment.

This requires you to divide the existing segment into two segments by adding a PDM. For this example, a TM5SPS1F (internal fuse of 6300 mA max.) between the TM5SDI4A and TM5SDO4TA electronic modules is needed.

The first 24 Vdc I/O power segment begins with the embedded DI12DE module and finishes with the TM5SDI4A expansion module once the PDM is installed.

The second 24 Vdc I/O power segment begins with the TM5SPS1F PDM and finishes with the TM5SDO2R expansion module.

The following table shows, the current supplied and consumed in mA on the 24 Vdc I/O power segment after the addition of the PDM:

The total current consumed on the first 24 Vdc I/O power segment is 5011 mA and does not exceed the 6300 mA capacity of this segment.

The total current consumed on the second 24 Vdc I/O power segment is 5708 mA and does not exceed the 6300 mA capacity of that segment.

The next step is to calculate the current consumed on the TM5 power bus to validate the configuration of this example.

Current Consumed on the TM5 Power Bus

The controller generates 400 mA on the TM5 power bus to supply expansion slices. The TM5 power bus begins with the TM5SAI4L expansion module and terminates with the TM5SDO2R expansion module.

The following table shows, the current supplied and consumed in mA on the TM5 power bus:

The total current consumed on the TM5 power bus is 642 mA, and exceeds the 400 mA capacity of the segment.

You must supplement the TM5 power bus by substituting the TM5SPS1F PDM with a TM5SPS2F type PDM .

The CPDM and the TM5SPS2F PDM provide 1576 mA (400 mA + 1176 mA) of current to the TM5 power bus.

The following table shows, the current supplied and consumed in mA on the TM5 power bus:

The total current consumed on the TM5 power bus is 602 mA, and does not exceed the 1576 mA capacity of the TM5 power bus.

The preceding table shows the final configuration of the example with the current supplied and consumed in mA on the TM5 power bus and the 24 Vdc I/O power segments.