Product Overview

F261 Series Fluid Flow Switches Product Bulletin4
The red terminal is the Common. Red to Yellow closes
on flow increase. Red to Blue closes on flow decrease.
Table 2: F261 Switch Action
Flow Action Switch Closure
Increase Red to Yellow
Decrease Red to Blue
Figure 3: F261 Control Switch Action
Red
Yellow
Blue
Decrease in Flow
Above Setpoint
Increase in Flow
Above Setpoint
Table 3: Flow Rates for Standard Models, 1-3 in. Paddles
GPM (m
3
/hr) Required to Activate Switch for Pipe Size (in.)
1
1-1/4
1
1-1/2
1
2
2-1/2
2
3
4
3
5
3
6
3
8
3
Minimum
Adjustment
Flow
Increase
(Close
R to Y)
4.20
(0.95)
5.80
(1.32)
7.50
(1.70)
13.7
(3.11)
18.0
(4.09)
27.5
(6.24)
65.0
(14.8)
125
(28.4)
190
(43.2)
375
(85.2)
Flow
Decrease
(Close
R to B)
2.50
(0.57)
3.70
(0.84)
5.00
(1.14)
9.50
(2.16)
12.5
(2.84)
19.0
(4.32)
50.0
(11.4)
101
(22.9)
158
(35.9)
320
(72.7)
Maximum
Adjustment
Flow
Increase
(Close
R to Y)
8.80
(2.0)
13.3
(3.02)
19.2
(4.36)
29.0
(6.59)
34.5
(7.84)
53.0
(12.0)
128
(29.1)
245
(55.6)
375
(85.2)
760
(173)
Flow
Decrease
(Close
R to B)
8.50
(1.93)
12.5
(2.84)
18.0
(4.09)
27.0
(6.13)
32.0
(7.27)
50.0
(11.4)
122
(27.7)
235
(53.4)
360
(81.8)
730
(166)
1. Values for 2 in. paddle trimmed to pipe.
2. Values for a 3 in. paddle trimmed to fit pipe.
3. Values calculated for a factory-installed set of 1, 2, and 3 in. paddles.