Emerson PACSystems RSTi-EP User Manual

User Manual Section 3
GFK-2958L May 2021
Configuration 33
Module
no.
Part
number
I
SYS
I
IN
I
OUT
I
S
I
L
Simultaneity
factor
g
Cumulative
current
demands of
the input
current path
Cumulative
current
demand of the
output power
path network
adapter
Cumulative
current
demand of
the EP-7641
output power
path
I
OUT
I
S
I
L
Power consumption from output current path
Current demand of the connected sensors
Current demand of the connected actuators
The current demand is just under 10 A. The output current path must therefore be refreshed before the
11th module.
10 A is supplied by the EP-7641 module. The 1.81 A calculated as remaining after the 10th module must not
be added to the 10 A after the EP-7641 module!
3.7.1 Calculation of Power Loss
The power loss of the network adapter is calculated as follows:
Pnetwork adapter = P0 + N * Pmod + Iin *
Δ
uin + Iout *
Δ
uout
P
0
Static power loss in the network adapter
2.3 W
N
Number of modules
P
mod
Power loss due to module supply from the system
current path
0.02 W
P
module
Maximum power loss module
I
in
Current fed in through the input current path
ΔV
in
Voltage drop across the contacts in the input current
path
0.18 V
I
out
Current fed in through the output current path
ΔV
out
Voltage drop across the contacts in the output current
path
0.18 V
The power loss of a RSTi-EP station is calculated using the power loss of the network adapter
and the power loss of the individual modules. It depends on the current in both current
paths. It is assumed that there is a maximum power loss of 2 watts for the module
Maximum values were assumed for these calculations. If you need detailed calculations,
please contact Emerson technical support or Global Care
https://www.emerson.com/Industrial-Automation-Controls/support.
P
station
= P
network adapter
+ N * P
module
3.7.2 Calculation of Power Loss for Use in a Potentially
Explosive Atmosphere
The module specific data, needed to calculate the output power loss, is provided in the ATEX
certificate which you can download from https://www.emerson.com/Industrial-
Automation-Controls/support.

Emerson PACSystems RSTi-EP Specifications

General

Brand	Emerson
Model	PACSystems RSTi-EP
Category	Controller
Language	English