Emerson Process Management rosemount 3300 series manual Hdg=Rqhv, 0DLPXP

5HIHUHQFH￿0DQXDO￿

00809-0100-4811, Rev AA October 2002

Rosemount 3300 Series

'HDG￿=RQHV	The measuring range depends on probe type and properties of the product.
	The 8SSHU￿'HDG￿=RQH is the minimum measurement distance between the
	upper reference point and the product surface. The Upper Dead Zone varies
	between 4 - 20 in. (0.1 and 0.5 m) depending on probe type and product.

At the end of the probe the measuring range is reduced by the /RZHU￿'HDG￿ =RQH. The /RZHU￿'HDG￿=RQH￿also varies depending on probe type and

product.

Figure 2-5 illustrates how the measuring range is related to the Dead Zones:

Figure 2-5. Dead Zones

Upper Reference Point

8SSHU￿'HDG￿=RQH

20mA

%
100-	0D[LPXP￿
Range 0	0HDVXULQJ￿5DQJH

ZONES	/RZHU 'HDG￿=RQH
	4mA
DEAD

Table 2-2￿￿;￿. Dead ￿￿￿(￿￿￿￿!￿￿￿￿￿￿￿;￿￿(￿￿￿￿Zones for different probe types

Upper Dead	2	3.9 in. (10 cm)	7.9 in. (20 cm)	15.7 in. (40 cm)	13.8 in. (35 cm)	19.7 in. (50 cm)
Zone
	80	3.9 in. (10 cm)	7.9 in. (20 cm)	11.8 in. (30 cm)	7.9 in. (20 cm)	11.8 in. (30 cm)
Lower Dead	2	2 in. (5 cm)	2.8 in. (7 cm)	5.9 in. (15 cm)	3.9 in. (10 cm)	4.7 in. (12 cm)
Zone
	80	1.2 in. (3 cm)	2 in. (5 cm)	2 in. (5 cm)	2 in. (5 cm)	2 in. (5 cm)

127(

The measurement accuracy is reduced in the Dead Zones. It may even be impossible to make any measurements at all in those regions. Therefore the 4-20 mA set points should be configured outside the Dead Zones.

2-7