FFE 3171 Ex User manual

E plosionproof Vibration Switch
Type 3171 E
Installation and Operating
Manual
EN
1. Introduction
The type 3171 Ex is a low-cost, vibration-sensitive, safety switch for the protection of rotating
and reciprocating machinery in hazardous environments. t is adjusted to operate above the
machine's normal running levels of vibration, activating machine shut-down circuits and/or
alarms and to switch off the machine before catastrophic failure.
The switch detects vibration in all directions. Unbalanced forces created by failing machinery
contain both the fundamental frequency and harmonics. The switch responds by shutting off the
machine if any components of vibration exceed the set value.
The switch operates as follows:
• Mounted vertically on a vibrating machine, a steel ball is held by a permanent magnet into
a conical seat
• f the vibration of the machine is sufficient to cause the ball to detach from the magnetic
field of the magnet, it trips a latched lever, thus releasing a micro switch plunger so the
machine can be stopped
• The ball and lever are latched by pressing the reset button manually
• The SET LEVEL of the vibration switch is set by adjusting the gap between permanent
magnet and ball.
Consult the FFE website at www.ffeuk.com for the latest information on applications and any
new warnings that may affect installation or safety.
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2. arnings and Cautions
Read all Warnings and Cautions before nstallation and Set-up.
2.1 arnings
2.2 Cautions
ARNING !
• Risk of electric shock
• For electrical safety, the vibration switch must be earthed
• For your own safety, disconnect all electrical power to the vibrating machine and ensure the
vibrating machine cannot operate during installation. Follow all safety warnings of the
machine manufacturer
• To avoid corrosion inside the vibration switch keep enclosure sealed before and after
installation
• The Cable Entry Cap is for transport and storage and is not suitable for resisting ingress of
moisture if a vibration switch is installed in the field and not wired. Unless the switch is
immediately wired using a suitable cable gland, replace the Cable Entry Cap with Blanking
Plug 0051-002-01 (see accessories).
• For Ex compliance, ensure a minimum ingress protection of P54 when selecting cable
entry devices.
• To prevent equipment Ex protection being compromised, the user shall perform external
visual inspection to confirm agressive substances such as acidic liquids and gases or
solvents have not compromised metallic or polymeric materials.
2.3 EMC Requirements
• To ensure EMC requirements are met, it is recommended that SWA, M CC, screened
cable, or metal conduit be used, with suitable earthing.
2.4 Terminal Block
• For reference, terminal block type BK6 is certified in EC Certificate Sira 01ATEX3247U.
• Classification Ex II 2GD EEx e II.
• Voltage rating 275V, current rating 28A.
2.5 Product Label

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3. Mechanical Installation
3.1 Introduction
The following tools will be needed:
• 3mm hexagon key for lid screws
• 4mm hexagon key to adjust SET LEVEL
• Wire strippers and wire cutters
• 3mm flat blade torque screwdriver for terminal block electrical connections
• 5mm flat blade torque screwdriver for internal protective earth terminal
• Adjustable spanner to fit cable gland
• nstallation of the vibration switch shall only be carried out by qualified personnel
• Remove vibration switch from carton
• Vibration switch is factory set to 3 g, unless a preset switch has been ordered
• To reduce the risk of damaging internal components and wiring, installation and wiring must
be performed within a temperature range of -10°C to +50°C
• Do not allow moisture or other airborne contaminants inside the switch as they can cause
corrosion
• When closing the lid, ensure the seal is not lost or damaged.
• Explanation of Tamb*: To maintain T6 temperature classification the vibration switch
maximum surface temperature due to any combination of ambient temperature and heat
from attached machinery the operating current of the vibration switch (which can cause
internal heat generation) must be limited as shown in the graph and table below;

3.2 Mechanical Installation Details
The vibration switch must be fitted on the machine structure so that good transmission is ensured
from the likely source of excess vibration.
The vibration switch shall be firmly fixed in the vertical orientation shown in figure 1 to a vertical
surface of the vibrating machine using M5 fixings suitably resistant to vibration.
Figure 1: Mechanical installati n t the surface f the vibrating machine
VERT CAL
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51
Set Level Cap Transport
Plug
M5 fixings
in the two
places
M5 fixings
in the two
places
M20 x 1.5
Cable
Entry Cap
Switch
Rating
Label
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4. Electrical Installation
4.1 Introduction
• Do not exceed the switch contact ratings. The primary switching circuit is rated at 5 Amp
maximum and must be fused appropriately in line with the protected machine’s mains
supply and isolation device
• When connection is by a cord, the Earth wire connection must be longer than the Live and
Neutral wires, such that failure of the strain relief will cause the Earth wire to be the last
conductor interrupted
• To prevent water running down onto the vibration switch, add a ‘drip loop’ in any external
cabling
• For ambient temperatures below –10°C, use external wiring rated for the minimum ambient
temperature expected
• Tie-wrap wires to protect against vibration and use cable ties rated for the expected
ambient temperature.
x4 3mm hex
4.2 Electrical Installation - Details
• To avoid breaking the lid hinge, DO NOT push on the lid when fully open.
Figure 2: Bef re Installati n
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Figure 3: Electrical Installati n
• Wiring to the terminal block and to the small internal earth stud shall only be with the
stranded or solid copper conducitors size 0.75-2.5mm2
• Wiring to the large external earth stud shall only be with stranded or solid copper
conductors size 1.5mm2to 6.0 mm2
• Only one conductor shall be used to a terminal unless multiple conductors have been
joined in a suitable manner e.g. by a single insulated crimped bootlace ferrule
• Wiring to terminals shall be insulated for the appropriate voltage and this insulaton shall
extend to within at least 1mm of the metal of the terminal throat
• Tighten down the unused terminal block terminal
• Torque used terminal block terminals to 0.6 ± 0.1Nm
• Torque small internal earth stud to 1.2 ± 0.1Nm
• Torque large external earth stud to 2.0 ± 0.1Nm
• Ensure internal and external wiring does not cross over the terminal block terminals

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Figure 4a: Wiring C nfigurati n
Switches are shown in their reset state.
x4 3mm hex
1Nm max.
Check lever moves freely up and down.
Figure 5
Figure 4b: Typical Installati n - Circuit Diagram

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Remove SET
LEVEL CAP.
With machine running,
reset switch.
Tripped ?
Tripped ?
s an increase in
sensitivity required ?
Switch is set.
Retract SET LEVEL SCREW
steadily until tripped, then
advance 1/2 turn.
Y
Y
Y
N
N
N
Advance SET LEVEL SCREW
steadily 1/2 turn.
Reset switch.
Reset Machine.
5. Set-up Sequence
No adjustment is needed if the vibration switch has been ordered preset for your application.
Otherwise, the vibration switch is factory set accurately to 3g. For set up in the field, adjust SET
LEVEL so that the switch no longer trips in normal running with reasonable sensitivity to
excesssive vibration as follows:

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The SET LEVEL can be estimated by referring to the calibration curve in figure 6 and counting
the number of turns from the factory setting.
f the factory setting is lost, it can be approximated as 11.5 turns from flush.
Figure 6: Vibrati n Switch Calibrati n Curve.
FLUSH

6. Functional Test
To check correct set-up of the vibration switch, repeat set-up sequence section 5.
7. Maintenance
There are no user serviceable parts inside the vibration switch. Maintenance is not required
except for periodic external visual inspection of the following:
• Confirm lid screws and vibration switch M5 fixings to machine are tight
• Confirm cable gland is tight to the enclosure and adequately secures the cable
• Confirm security of wires to external earth stud, where used
• Visually check vibration switch supply cable is installed as per local regulations and
undamaged
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8. Accessories
Part Number Description Picture
1000-026 L D ASSEMBLY - TYPE MR
G003 GLAND M20 TRS C P
S171 SEAL 400-024449041
1000-027 4MM HEX DR VER LONG
0051-002-01 BLANK NG PLUG P66/67
23640-083 ADAPTOR 20mm MALE
23640-085 CABLE GLAND F.P.
Document Number: 0044-059-01-EN
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