Dwyer UXF2 - Manual (Page 63)

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20mA
4mA
Hysteresis
4.5.5.3. Setting forward/reverse automatic 2 ranges
Description
z
The function measures the flow rate of either forward or reverse
flow while changing over the range corresponding to the flow
direction.
z The current output changes with the action range as illustrated on
the right.
z The hysteresis can be set to between 0 and 10% of the action
range.
z Upon setting DO1 or DO2 to "FLOW SPAN-2", a contact outputs
"SPAN-2" action. Select [ACTIVE ON] or [ACTIVE OFF]
separately (see Section 4.5.7.3.).
z After changing the range value, adjust zero point (see Section 4.5.1.).
z Settable range: r0.3 to 10 [m/s] in terms of flow velocity in piping for any of SPAN-1 and SPAN-2.
* The piping parameters and FLOW UNIT must be set beforehand.
* If a value beyond the settable range is inputted, "INPUT ERROR" appears and then last setting is resumed.
* If "FLOW UNIT" has been changed after setting the range,set the range setting again.
* When FLOW SPAN-2 is not used (in the case of single range), set “0” for FLOW SPAN-2.
Note: 1. The flow rate unit is as selected by "FLOW UNIT in the "MEASUREMENT SETUP" mode. Before
range setting, set the "FLOW UNIT" (see Section 4.6.2.).
For actual keying, refer to the typical operation indicated below. Set the parameter protection to OFF beforehand
(Section 4.4.1).
Typical operation Set "FLOW SPAN-1" to 20 [m 3 /h], "FLOW SPAN-2" to -10 [m 3 /h], and "HYSTERESIS" to 7%.
* Set the piping parameters and "FLOW UNIT" beforehand.
Keying order Description Indication
ź
Pressed twice to indicate "OUTPUT SETUP". OUTPUT SETUP
ENT
ź
Pressed to indicate "ZERO ADJUST". ZERO ADJUST
CLEAR
ź
Pressed 4 times to indicate "RANGE". RANGE
FLOW RATE
ENT
ź
Pressed to blink the cursor. RANGE
FLOW RATE
ENT
ź
Pressed to indicate "FLOW SPAN-1". FLOW SPAN-1
50.0000 m3/h
ENT
ź
Pressed to blink the cursor. FLOW SPAN-1
0 050.0000 m3/h
ź
Pressed repeatedly until the cursor is positioned at "5". FLOW SPAN-1
00
5 0.0000 m3/h
ź
Pressed repeatedly until "2" appears.
Note: To change the decimal point position, align the
cursor with a place to change to, and press
key likewise
FLOW SPAN-1
00
2 0.0000 m3/h
ENT
ź
Pressed to register it. FLOW SPAN-1
½½ COMPLETE ½½
Ļ
BULLETIN F-70