72
POSITIVE OPENING OPERATION
A limit switch complies to this specification when
all the normally closed contact elements of the
switch can be changed, with certainty, to the
open position (no flexible link between the moving
contacts and the operator of the switch, to which
an actuating force is applied). Positive opening
does not apply to NO contacts. Control switches
with positive opening operation can be equipped
with either slow-break or snap-action contacts.
In order to use different contacts on the same
switch, it is necessary to electrically separate
them; otherwise only one contact can be used.
Every positive opening control switch must be
marked on the external housing with the symbol .
DOUBLE INSULATION
Limit Switches
FA - FT - FT1R - Safety - FCT - Astra Series
Terminology
Materials of group II, according to IEC536,
are made with double insulation. This consists
of doubling the insulation capability by means
of an additional divider in order to eliminate any
electrical shock risk and avoid the need for any
additional protections.
SNAP-ACTION CONTACTS
Snap action contacts are characterised by
different tripping and resetting points
(differential travel).
The displacement speed of the moving
contacts is independent to the speed of the
operator. This feature ensures satisfactory
electrical performance in applications
involving low speed actuators.
Approach travel
Unactuated state
Positive opening
SLOW-BREAK CONTACTS
APPLICATIONS
AC-15: control of an electromagnet on a.c.,
test 10 le/le.
AC-13: control of an electromagnet on d.c.,
test le/le.
Contact activated
Contact in stand-by
CONTACT BLOCKS CONFIGURATION
13
21
14
22
Zb
The two moving contacts are
electrically insulated
13
11
14
12
Za
Contacts with same
polarity
Contact blocks with 4 terminals must be marked
with Za or Zb symbols as shown
in the picture below.
ACCORDING TO IEC/EN60947-5-1
TERMINALS
For limit switches with metal housing, the fixing point
of the earth conductor must be marked and must
be positioned inside the housing next to the cable
entry.
Slow break contacts are characterised by identical tripping and resetting
points. The displacement speed of the moving contacts is equal,
or proportional, to the speed of the operator. The opening distance
is also dependent on the distance travelled by the operator. 73
It is the minimum force/momentum that must be applied by
the actuator for the contacts to trip.
0 3.1 5.3
8.2
10.5 mm
21-22
13-14
21-22
13-14
21-22
13-14
21-22
13-14
0 20
° 33°
49
°
78
°
21-22
13-14
0
2.1 3.7
6.0 mm.
3.0
0 3.1 5.3
8.2
10.5 mm
21-22
13-14
21-22
13-14
21-22
13-14
21-22
13-14
0 20
° 33°
49
°
78
°
21-22
13-14
0
2.1 3.7
6.0 mm.
3.0
Limit Switches
FA - FT - FT1R - Safety - FCT - Astra Series
Terminology
TECHNO-CONTROL EQUIPMENT
MINIMUM OPENING
FORCE/MOMENTUM
MINIMUM POSITIVE OPENING
FORCE/MOMENTUM
It is the minimum force/momentum that must be applied by
the actuator to guarantee the positive opening of NC contacts.
L
P
o
P
A
P
P
P
R
C
CP
C1
F1
CL
C2
C3
C4
C
C
Maximum travel of the actuator in mm
C
Maximum travel
of the actuator in degrees
C
L
P
P
C
P
C
1
C
3
C
4
Tripping
Resetting
21-22
13-14
21-22
13-14
C
L
P
P
C
P
C
1-1
C
1-2
21-22
13-14
Tripping
Resetting
Rest position
Position of the actuator when no
external force is applied.
P
O
Tripping point of contact
Position of the actuator, with force
F1 applied, in which the contacts
leave the stand-by position.
P
A
Positive opening position
Position of the actuator when there
is positive opening.
P
P
Resetting position
Position of the actuator
when the contacts are back
in their non actuated
position.
P
R
Maximum travel position
Maximum travel of the actuator
when the force F1 is applied.
L
Tripping travel
Distance between the Po and
P
A
positions.
C
1
Tripping travel for snap-action
contacts
Tripping travel for slow-break
contacts
Positive opening tripping travel
Minimum travel of the actuator
from the Po position to guarantee
positive opening of NC contacts.
C
P
Extra tripping travel
Distance between PA and the
maximum travel L.
C
2
Differential travel (C1-C4)
Distance between P
A
and P
R
C
3
Resetting travel
Distance between P
R
and Po
C
4
Maximum travel
Distance between Po and the maxi-
mum travel L.
C
L
NOTE: for slow-break contacts, C3=01, C1-1=Tripping and resetting travel of contacts 21-22, C1-2- Tripping and resetting travel of contacts 13-14
Examples
FA134Z11
(snap-action contacts)
FA138Z11
(snap-action contacts)
FA131X11
(slow break contacts)
Tripping travel in mm/
cam linear movement
Tripping travel in degrees/
lever rotary movement
Tripping travel in mm/
plunger linear movement 74
FA134W20
0
21-22
13-14
5.3 8.2
3.0
9.6 mm
168 gr. 1 pcs.
75
Ø 8
20
12.5
30
°
Ø 11
31
AM 1 F12
20
25
86
12.5 3.5
TYPE
OF OPERATOR
EN50047
FA131Z11
FA1 Series
IP66 die-cast aluminium type
EN50047
-
STEEL ROLLER
PLUNGER
Standard Positive opening NC contacts
Minimum tripping force
Minimum positive opening force
WEIGHT gr. MIN. PACK QTY.
DIMENSIONS
186 gr. 1 pcs.
186 gr. 1 pcs.
175 gr. 1 pcs.
PA ROLLER LEVER PLUNGER
VERTICAL ACTUATION
SHORT STEEL
END PLUNGER
PA ROLLER LEVER PLUNGER
HORIZONTAL ACTUATION
Limit Switches
FA131
FA134
FA132
FA133
1 cable entry
M16x1.5
Z11
1NC-1NO
Snap action
Zb
Z02
2NC
Snap action
11
12
21
22
W02
2NC
Slow break
11
12
21
22
W20
2NO
Slow break
13
14
23
24
Y11
1NC-1NO
overlapping
Slow break
Zb
Zb
Zb
Zb
13
14
21
22
X11
1NC-1NO
Slow break
Zb
13
14
21
22
13
14
21
22
15
30
12
30
7
24
7
24
0
21-22
13-14
21-22
13-14
1.3 2.5
4.1
5.6 mm
FA131W02
0
11-12
21-22
1.5 3.1
5.6 mm
FA131W20
0
13-14
23-24
1.4
5.6 mm
FA131Z02
0
11-12
21-22
11-12
21-22
1.3 2.4
4.0
5.6 mm
FA131Y11
0
21-22
13-14
2.9 4.5
1.5
5.6 mm
0
21-22
13-14
1.6 3.2
2.5
5.6 mm
FA134Z11
FA134W02
FA134Z02
FA134Y11
FA134X11
FA132Z11
0
21-22
13-14
21-22
13-14
4.9 9.0
14.5 21.0 mm
FA132W02
0
11-12
21-22
5.7 10.2
21.0 mm
FA132W20
0
13-14
23-24
5.3
21.0 mm
FA132Z02
0
11-12
21-22
11-12
21-22
5.1 8.6
13.1 21.0 mm
FA132Y11
0
21-22
13-14
10.2 14.6
5.4
21.0 mm
FA132X11
0
21-22
13-14
6.0 10.5
8.6
21.0 mm
FA133Z11
FA133W02
FA133W20
FA133Z02
FA133Y11
FA133X11
FA131X11
0
21-22
13-14
21-22
13-14
4.9 9.0
14.5 21.0 mm
0
21-22
13-14
6.0 10.5
8.6
21.0 mm
0
21-22
13-14
10.2 14.6
5.4
21.0 mm
0
11-12
21-22
11-12
21-22
2.5 4.5
7.4
9.6 mm
0
11-12
21-22
11-12
21-22
5.1 8.6
13.1 21.0 mm
0
11-12
21-22
5.7 10.2
21.0 mm
0
11-12
21-22
3.0 5.9
9.6 mm
0
13-14
23-24
2.8
9.6 mm
0
13-14
23-24
5.3
21.0 mm
0
21-22
13-14
3.2 6.0
4.6
9.6 mm
0
21-22
13-14
21-22
13-14
2.5 4.7
7.6
9.6 mm
-
32.5
14.5
Pg 13.5
1/2" NPT
M16x1.5
M20x1.5
12.5
30.3
Ø 4
20
22
55
4
ø 12.5
12.5
30
°
5
92
39
31
20
30
°
20
21
29
ø 12.5
19.5
39
12.5 5
92 75
Limit Switches
FA1 Series
IP66 die-cast aluminium type
TECHNO-CONTROL EQUIPMENT
FA141W20
0
21-22
13-14
35
°
18
°
74
°
235 gr. 1 pcs.
53
36
5.5
15
108
45
40
ø 18
17.5
ø 50
66.5
17.5
36
9
43.5
51
121.5
45.5
41
34
5.5
42
ø 18
100.5...172.5
45.5...117.5
17.5
52
44.5
32.5
9
125...183.5
17.5
ø 50
70...128.5
TYPE
OF OPERATOR
-
FA138Z11
-
-
-
50 Ø RUBBER
ROLLER LEVER
Standard Positive opening NC contacts
Minimum tripping force
Minimum positive opening force
WEIGHT gr. MIN. PACK QTY.
DIMENSIONS
245 gr. 1 pcs.
265 gr. 1 pcs.
255 gr. 1 pcs.
VARIABLE LENGTH 50 Ø
RUBBER ROLLER LEVER
18 Ø
PA ROLLER LEVER
VARIABLE LENGTH 18 Ø
PA ROLLER LEVER
FA138
FA141
FA139
FA140
1 cable entry
M16x1.5
Z11
1NC-1NO
Snap action
Zb
Z02
2NC
Snap action
11
12
21
22
W02
2NC
Slow break
11
12
21
22
W20
2NO
Slow break
13
14
23
24
Y11
1NC-1NO
overlapping
Slow break
Zb
13
14
21
22
X11
1NC-1NO
Slow break
Zb
13
14
21
22
13
14
21
22
0.10
0.32
0.10
-
0.10
-
0.10
-
0
21-22
13-14
21-22
13-14
17
° 31°
47
° 74°
FA138W02
0
11-12
21-22
19 37
74
FA138W20
0
13-14
23-24
18
°
74
°
FA138Z02
0
11-12
21-22
11-12
21-22
17 30
46 74
FA138Y11
0
21-22
13-14
35
° 51°
18
°
74
°
0
21-22
13-14
21
° 37°
30
°
74
°
FA141Z11
FA141W02
FA141Z02
FA141Y11
FA141X11
FA139Z11
0
21-22
13-14
21-22
13-14
17
° 31°
74
°
FA139W02
0
11-12
21-22
19 74
FA139W20
0
13-14
23-24
18
°
74
°
FA139Z02
0
11-12
21-22
11-12
21-22
17 30
74
FA139Y11
0
21-22
13-14
35
°
18
°
74
°
FA139X11
0
21-22
13-14
21
°
30
°
74
°
FA140Z11
FA140W02
FA140W20
FA140Z02
FA140Y11
FA140X11
FA138X11
0
11-12
21-22
11-12
21-22
17 30
74
0
11-12
21-22
19 74
0
13-14
23-24
18
°
74
°
0
21-22
13-14
21
°
30
°
74
°
0
21-22
13-14
21-22
13-14
17
° 31°
74
°
32.5
14.5
Pg 13.5
1/2" NPT
M16x1.5
M20x1.5
12.5
30.3
Ø 4
20
22
55
4
0
21-22
13-14
21-22
13-14
17
° 31°
74
°
0
11-12
21-22
19 74
0
13-14
23-24
18
°
74
°
0
11-12
21-22
11-12
21-22
17 30
74
0
21-22
13-14
35
°
18
°
74
°
0
21-22
13-14
21
°
30
°
74
°
Zb
Zb
Zb 76
IP66 die-cast aluminium type
FA1 Series
FA136W20
235 gr. 1 pcs.
Ø 8
15.5
195
128
15.5
Ø 1.3
195
128
42
36
170
Maxi 232.5
Maxi 177.5
17.5
ø 3
5.5
TYPE
OF OPERATOR
-
FA135Z11
-
-
CATS WHISKER
Standard Positive opening NC contacts
Minimum tripping force
Minimum positive opening force
WEIGHT gr. MIN. PACK QTY.
DIMENSIONS
245 gr. 1 pcs.
255 gr. 1 pcs.
SPRING LEVER
WITH TIP IN PA
3 Ø STEEL
ROD LEVER
FA135
FA136
FA137
1 cable entry
M16x1.5
Z11
1NC-1NO
Snap action
Zb
Z02
2NC
Snap action
11
12
21
22
W02
2NC
Slow break
11
12
21
22
W20
2NO
Slow break
13
14
23
24
Y11
1NC-1NO
overlapping
Slow break
Zb
13
14
21
22
X11
1NC-1NO
Slow break
Zb
13
14
21
22
13
14
21
22
0.10
-
0.10
-
0.10
-
0
21-22
13-14
21-22
13-14
12
° 23°
36
°
FA135W02
0
11-12
21-22
14
°
21
°
36
°
FA135W20
0
13-14
23-24
13
°
36
°
FA135Z02
0
11-12
21-22
11-12
21-22
12 22