SMAR ld301, Operation And Maintenance Instruction Manual

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LD301- Operation and Maintenance, Instruction manual
3.10
NOTE :
F(t) indication is activated every time the totalized value is shown on the digital
display.
Figure 3.3 – Typical Monitoring Mode Display Showing the Total, in this case
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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.
ATTENTION :
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 dm
3
/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%.
The PID implementation algorithm is:
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