LD301 - Operation and Maintenance, Instruction Manual
3.12
TOTALIZATION INCREMENT - this is used to convert the flow rate base unit into a multiple unit of
mass or volume. For example, a flow rate totalized in gallons/s may be converted to a volume in m3;
a mass flow rate of g/s may be converted to kilos, etc.
TOTALIZATION UNIT - this is the engineering unit. It shall be associated to the totalized value. It
may be a standard unit or a special unit with up to five characters.
WARNING
The totalizer shall be disabled so that any of these parameters can be configured.
The largest totalized value is 99.999.999 totalizing units. When the totalization is displayed, the most
significant part is shown on the numeric field, and the less significant part is shown on the alphanumeric
field. Figure 3.6 shows a typical display indication.
NOTE
F(t) indication is activated every time the totalized value is shown on the digital display.
+ SIGNIFICANT
- SIGNIFICANT
F ( t )
Figure 3.6 – Typical Monitoring Mode Display Showing the Total, in this case 19.6708.23
The following services are associated with the Totalizer:
INITIALIZATION - Totalization is reinitialized from value "0";
ENABLING / DISABLING - this allows the totalization function to be enabled or disabled.
WARNING
From Version V6.00 on, with the use of the new main board, the totalized value is persistent, i.e.,
there is no longer the risk of losing this information in case of power failure.
Example: A differential pressure of 0 - 20 inH2O represents a flow of 0 - 6800 dm
3
/minute.
In CONF set Lower = 0 inH2O and Upper = 20 inH2O.
In order to adjust the MAX._FLOW, the maximum flow must be converted to cubic decimeters per
second: 6800 / 60 = 113.3 dm3 /s.
The selection of the totalization unit (U_TOTAL) is made in function of the maximum flow and the
minimum time allowable for the counter overrun, i.e., the time required for the totalization to reach
99.999.999.
In the example, if U_TOTAL = 1, the totalization increment is 1 dm
3
. The time required for the overrun
with maximum flow is 245 hours, 10 minutes and 12.5 seconds.
On the other hand, in case a TOTALIZATION INCREMENT equal to 10 is used, the totalized unit will be
deciliter (dal) and the totalizer will receive one increment at every 10 dm
3
. Considering the maximum
flow rate (113.3 dm
3
/s), the totalizer will reach its maximum value and return to zero in 102 days, 3
hours, 42 minutes and 5.243 seconds.
PID Controller Configuration
The LD301 may be factory -configured to work as Transmitter only or as Transmitter / Controller. In case
the LD301 is configured as a Transmitter / Controller, the end user may change its operation mode at
any time simply by configuring an internal status variable.
As a PID Controller, the LD301 may run a PID type control algorithm, where its 4 to 20 mA will represent
the status of the Manipulated variable (MV). In such a mode, output is 4 mA when the MV = 0% and 20
mA when MV= 100%.
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