12
Planning of the I/O configuration requires careful calculation of the power required for each chassis.
Certain I/O cards require 24 VDC on the chassis backplane. The RTP Power Supply can provide this
power internally, or it can be supplied by the BPEXTV connections. To determine, if the internal supply is
sufficient, a power calculation for each chassis must be performed as shown in the Table 1: Total card
current consumption on 5 V and 24 V is calculated by multiplying the voltages with quantity within the
chassis installation (blue cells). Then total consumption for 5 V and 24 V is calculated (yellow cells). The
5 V consumption, marked with note
(1)
in Table 1, must be limited to 15 Amperes. If using AC main power
and if the 24 V consumption, is above 3.15 Amperes, then BPEXTV on Main Terminal Block shall be
wired also to supply 24 V externally. However, even in this situation, the total consumption of 24 V
marked with note
(2)
in Table 1, must not exceed 10 Amperes. The same rules apply to the 24 VDC
Power Supply module, except that the BPEXTV on Main Terminal Block must be always wired.
Table 1: Example Chassis Current Consumption Calculation in Amperes
Per Card
Total Consumed
Quantity Description
5 V
24 V
5 V
24 V
Node Processor (3000/06)
1.75
0.00
Node/Chassis Processor (3200)
1.75
0.00
1
Chassis Processor
1.20
1.20
MODBUS TCP/IP
2.30
0.00
12-Ch. Relay Output
0.85
0.00
8-Ch. Thermocouple
0.50
0.15
0.00
0.00
8-Ch. Low Level Analog Input
0.50
0.15
0.00
0.00
8-Ch. High Level Analog Input
0.50
0.15
0.00
0.00
8-Ch. RTD
0.30
0.25
0.00
0.00
16-Ch. AC Digital Output
0.60
0.00
HART
1.40
0.00
MODBUS Serial
1.40
0.00
2-Ch. Servo Card
1.40
0.55
0.00
0.00
16-Ch. Analog Output
0.50
0.675
0.00
0.00
32-Ch. Analog / Digital Input
0.40
0.10
0.00
0.00
32/24/18-Ch. DC Digital Output
0.20 0.055
0.00
8-Ch. Counter
1.40
0.15
0.00
0.00
32-Ch. Relay Output
1.10
0.00
0.00
1
Standard Chassis Fans
0.69
0.69
Micro Chassis Fans
0.23
0.00
Total Consumed Current
1.20
(1)
0.69
(2)
AC Power Supply Current Limit
15.00
3.15
BPEXTV Current Limit
10.00
DC Power Supply Current Limit
15.00
