Reference Manual
00809-0100-4841, Rev. AA
May 2007
Rosemount 3490 Series
4-68
Figure 4-41. Navigating to the
TOTALISER Menu
Totalising examples NOTE:
Totalisers are set-up to operate with an input of flow in units of flow/second.
Example 1
Consider a flow measurement application where the PV value is a flow rate in
units of litres per second and the maximum flow rate is 200 litres per second.
For the Totaliser to count every m
3
(1000 litres), the Totaliser Factor
(P530/P532) must be set to 1000, and the Totaliser Units (P531/P533) must
be set to m
3
.
The 3490 Series Control Unitt will then add 1 to the Totaliser Count (D828 /
D829) for every 1000 litres that flows. The Totaliser Count (D828 / D829) will
be automatically displayed in m
3
by setting the Totaliser Units.
Figure 4-42 shows how the "Totaliser" Wizard is used to set-up this totalising
example. It is assumed the PV value is a flow rate in units of litres per second,
which is set-up using the "Duty" Wizard.
In addition, for this example:
• Relay 4 (RL4) will be a Totaliser relay and output a 100 millisecond pulse
(P534) for every m
3
added to the Totaliser Count.
(To set-up this manually, see Section “Relays“ on page 4-40.)
• Relay 3 (RL3) will be a Sampler relay that will output a pulse for every
200th m
3
added to the Totaliser Count.
(To set-up this manually, see Section “Relays“ on page 4-40.)
• The Totaliser will not freeze while a digital input is active.
The SELECT INSTRUMENT menu is skipped automatically if there are no HART transmitters.
(Model 3491 screens are shown.)
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