ABB CM30 - Functions

ControlMaster CM30 and CM50
Universal process controllers,
1
/4 and
1
/2 DIN 7 Advanced Level
IM/CM/ED–EN Rev. B 51
7.6.1 Calculating the Totalizer Count Rate Manually
Analog Mode
Example 1:
Eng Hi = 2500 l/m. Totalizer required to increment in m
3
.
Volume unit conversion: 1 l = 0.001 m
3
.
Source time units = minutes, count rate units = seconds.
Time unit conversion: 1 min = 60 s.
Example 2:
If the input source is at a fixed rate of 2500 l/min, the totalizer increments at 0.04167 m
3
/s.
If the input source is reduced to a fixed rate of 1250 l/min, the totalizer increments at:

Digital Mode
The count rate setting determines the scaling of the digital input pulses.
For example, with a Count Rate = 100 totalizer units / pulse, 5 digital input pulses increment the totalizer
from 0 to 500 in 100 unit steps:
Count Rate =
Eng Hi (of source) x volume unit conversion
time unit conversion
Count Rate =
2500 x 0.0001
60
= 0.04167 m
3
/s
1250
2500
x 0.04167 = 0.0208 m
3
.
500
400
300
200
100
0
1 Minute
Units
Totalizer Value
Input Signal
t
t
On
Off
1 Minute