Instructions

Power manual for MACX Analog, MACX Analog Ex, MACX PL, MINI Analog, and MINI Analog Pro signal conditioners
56 PHOENIX CONTACT 105810_en_01
Figure 5-8 Supply by means of redundant power supplies
Example for supply via a TC-MACX-MCR-PTB power terminal block
16 MACX MCR-SL-RTD-I temperature transducers (Order No. 2865065), 20 MACX MCR-
SL-NAM-R NAMUR signal conditioners (Order No. 2865997), and 13 MACX MCR-EX-SL-
RPSSI-I Ex i repeater power supplies (Order No. 2865340) are to be supplied at an operat-
ing voltage of 24 V DC.
First determine the current consumption of the modules from the package slips. For the tem-
perature transducers it is 40 mA per module and for the NAMUR signal conditioners it is
21 mA. The intrinsically safe repeater power supplies require 60 mA each.
Then determine the maximum total current consumption of all 49 modules.
The total current consumption of 1840 mA is less than the maximum permissible current for
supply via the TC-MACX-MCR-PTB. To ensure that the 2500 mA fuse to be connected up-
stream of the TC-MACX-MCR-PTB definitely trips in the event of a short circuit, the 24 V DC
+
–
PSU
LFD
+24V
14
12
11
+24V
–
+
+24V
–
+
Fault out
PWR2
PWR1
3.3
3.2
3.1
2.3
2.2
2.1
1.3
1.2
1.1
GND
N.C.
GND
2500 mA
+
–
PSU
2500 mA
Faultsignal
TBUS
Modul
1
Modul
n
I = n * I + n * I + n * I + ...
1 module12module23module3
I= 16 * 40 mA + 20 * 21 mA + 13 * 60 mA = 1840 mA < 2000 mA