Navigation

TIP: Load power supply (PM) x System power supply (PS)

Created by: Denilson Pegaia at: 2/28/2013 10:44 AM (8 Replies)

Rating (4)

Thanks 25

9 Entries

2/28/2013 10:44 AM

Rate (3)

Denilson Pegaia

Platinum Expert

Joined: 9/23/2005

Last visit: 12/8/2023

Posts: 4284

Rating:

(1381)

Hi,

To understand the necessity and the existence of two different type of power supply, t we need to know that e.g. the modules are divided in two main circuits:

1 - A field circuit that effectively has electrical contact with the field.
2 - An intern circuit that exchange data with CPU (backplane BUS circuit).

To avoid that a problem in field damages all modules of the CPU, this circuits are normally isolated (for example, by optocouplers). So, if an undesired voltage appears in the module connector, the damage of it is not propagated to others modules. This strategy is used since S5 controllers with success.

A consequence of this strategy is that the modules should receive two power supplies: one for the “field” electronic and other for the “backplane” circuit. Generally (for the other PLC families), the internal circuits are supplied by the CPU, and it means that the CPU power limitation lead to limitations to number / type of modules that could be used together with the CPU.

The S7-1500 family innovate this concept permitting that the internal supply could be “buster” by external power supply.

As consequence of this innovation, the S7-1500 has two types of power supplies:

Load (Module) power supply (PM)
The load power supply feeds the input and output circuits of the modules and the sensors and actuators. You also need a load power supply, if necessary to provide the CPU and the system power supply with the required 24 V DC.

The PM is connected to module terminals connector.

System power supply (PS)
The system power supply delivers only the required system voltage for the internal backplane. This system voltage supplied parts of the module electronics and LEDs that indicate the module status (RUN, ERROR, MAINT).

TIPS:
It is possible to connect one PS on left or in right side of the CPU (optional). When used on the left side of the CPU, the PS supply the CPU and the modules on right side of them (the CPU doesn’t supply any module, and takes also the power from PS). When used on the right side of the CPU, the PS start a “new” power circuit, independently of the CPU supply. It is possible to use up two PS between modules, on the right side of the CPU.

If the PS is not connected, not ON, or if the real configuration differ so much of the projected, the CPU could not be able to supply all modules. In this case, the CPU turn off all bus, register the event on diagnostic buffer and tries to start again (STOP LED flashes).

STEP7 checks if the configuration is consistent (Device View, CPU/PS properties)

As Tomb Rule, a CPU could supply at least 10W of power, and an IO module takes at maximal, 1.15W (CP,CM takes more). That means that you can use up to 8 modules without to check if an additional PS is necessary.

The follows tables shows the power supply capacity in the three situations: CPU stand alone, with PS on left side of the CPU and with PS in a new circuit (on right side of the CPU)

Option 1: CPU standalone

CPU	MLFB	CPU properties-> system power supply	System Power Suppy	MLFB	Power avaliable for expansion modules [W]
1511-1	6ES7 511-1AK00-0AB0	Connection to supply voltage L+	-	-	10
1513-1	6ES7 513-1AL00-0AB0	Connection to supply voltage L+	-	-	10
1516-3	6ES7 516-3AN00-0AB0	Connection to supply voltage L+	-	-	12

Option 2: System Power Suppy on left side of the CPU

CPU	MLFB	CPU properties-> system power supply	System Power Suppy	MLFB	Power avaliable for expansion modules [W]
1511-1	6ES7 511-1AK00-0AB0	No connection to supply voltage L+	25W, 24V DC	6ES7 505-0KA00-0AB0	19,5
1511-1	6ES7 511-1AK00-0AB0	No connection to supply voltage L+	60W 24/48/60VDC	6ES7 505-0RA00-0AB0	54,5
1511-1	6ES7 511-1AK00-0AB0	No connection to supply voltage L+	60W 120/230VAC/DC	6ES7 507-0RA00-0AB0	54,5
1513-1	6ES7 513-1AL00-0AB0	No connection to supply voltage L+	25W, 24V DC	6ES7 505-0KA00-0AB0	19,5
1513-1	6ES7 513-1AL00-0AB0	No connection to supply voltage L+	60W 24/48/60VDC	6ES7 505-0RA00-0AB0	54,5
1513-1	6ES7 513-1AL00-0AB0	No connection to supply voltage L+	60W 120/230VAC/DC	6ES7 507-0RA00-0AB0	54,5
1516-3	6ES7 516	No connection to supply voltage L+	25W, 24V DC	6ES7 505-0KA00-0AB0	18,3
1516-3	6ES7 516	No connection to supply voltage L+	60W 24/48/60VDC	6ES7 505-0RA00-0AB0	53,3
1516-3	6ES7 516	No connection to supply voltage L+	60W 120/230VAC/DC	6ES7 507-0RA00-0AB0	53,3

System Power Suppy on right side of the CPU

System Power Suppy	MLFB	Power avaliable for expansion modules [W]
25W, 24V DC	6ES7 505-0KA00-0AB0	25
60W 24/48/60VDC	6ES7 505-0RA00-0AB0	60
60W 120/230VAC/DC	6ES7 507-0RA00-0AB0	60

References:

Additional information about system power supplies and load power supplies is available in the manual "SIMATIC S7-1500 Automation System" in Entry ID: 59191792and in FAQ "How should you configure the system power supplies for the S7-1500 in STEP 7 (TIA Portal) so that all the connected modules are supplied?" (http://support.automation.siemens.com/WW/view/en/73191930?Datakey=47071380).

Last edited by: Pegaia at: 5/23/2013 12:32 PM

Last edited by: Pegaia at: 5/23/2013 12:28 PM

link of FAQ

Last edited by: Pegaia at: 3/1/2013 11:29 AM

Denilson Pegaia
Siemens Industry Sector
Technical Support

This contribution was helpful to

21 thankful Users

5/3/2016 6:39 AM	Rate (0)
AutoGen_250039 Posts: 4 Rating: (0)	Hi Mr.Denilson .., Is it possible to deliver power in following configuration . One power source to CPU module and another power source to other module as per attachment . Is it necessary to bond common 0V from different power supply .? Regards .., Tun Attachment CPU_Power.jpg (1742 Downloads)
AutoGen_250039 Posts: 4 Rating: (0)
Suggestion To thank Quote Answer
This contribution was helpful to 2 thankful Users a.cheraghi amuz2805

5/3/2016 1:01 PM	Rate (0)
Denilson Pegaia Platinum Expert Joined: 9/23/2005 Last visit: 12/8/2023 Posts: 4284 Rating: (1381)	Hi, Yes, you can supply the internal side (from CPU) and external side (IO modules connector), with different power supplies (e.g. you use different protections too). I suggest, however, that you interconnect the M of both power supplies (and if applicable, connect then to the ground).
	Denilson Pegaia Siemens Industry Sector Technical Support
Suggestion To thank Quote Answer
This contribution was helpful to 1 thankful Users Vivek Kansara

5/4/2016 4:46 AM	Rate (0)
AutoGen_250039 Posts: 4 Rating: (0)	Ok .. Got it Sir .. Thanks Very much ..
AutoGen_250039 Posts: 4 Rating: (0)
Suggestion To thank Quote Answer

8/19/2016 5:15 PM	Rate (1)
xsmart Bronze Member Joined: 11/17/2015 Last visit: 12/7/2023 Posts: 56 Rating: (15)	Hi! Will be power add up in case, when PS is installed at the left of CPU and the option "Connection to supply voltage L+" is selected (and external load power connected to CPU)? Portal shows, that it will Attachment 4.jpg (1217 Downloads)

Suggestion To thank Quote Answer

9/8/2016 3:07 PM	Rate (0)
Denilson Pegaia Platinum Expert Joined: 9/23/2005 Last visit: 12/8/2023 Posts: 4284 Rating: (1381)	Hi, You can add the power of the CPU to the PS. Thanks to Technical Support Germany to help us to clarify the question.
	Denilson Pegaia Siemens Industry Sector Technical Support
Suggestion To thank Quote Answer
This contribution was helpful to 1 thankful Users xsmart

10/25/2016 4:29 PM	Rate (0)
Min_Moderator Platinum Member Joined: 9/3/2014 Last visit: 3/13/2019 Posts: 4782 Rating: (123)	New question published by Karimat is split to a separate thread with the subject Power Supply setup. Best regards Min_Moderator

Suggestion To thank Quote Answer

3/1/2017 10:46 AM	Rate (0)
Ziemens Silver Member Joined: 3/2/2007 Last visit: 11/8/2023 Posts: 895 Rating: (5)	very useful information. thank you
	... thank you ...
Suggestion To thank Quote Answer

3/16/2017 11:24 AM	Rate (0)
Denilson Pegaia Platinum Expert Joined: 9/23/2005 Last visit: 12/8/2023 Posts: 4284 Rating: (1381)	it is a pleasure to help :)
	Denilson Pegaia Siemens Industry Sector Technical Support
Suggestion To thank Quote Answer

Share this page:

Share this page on...

Created by: Denilson Pegaia at: 2/28/2013 10:44 AM (8 Replies)

Rating (4) Thanks 25

9 Entries

Last edited by: Pegaia at: 5/23/2013 12:32 PM

Last edited by: Pegaia at: 5/23/2013 12:28 PM

Last edited by: Pegaia at: 3/1/2013 11:29 AM

This contribution was helpful to

Attachment

This contribution was helpful to

This contribution was helpful to

Attachment

This contribution was helpful to

9 Entries

All about SIMATIC S7-1500

Follow us on

Rating (4)

Thanks 25