Eriez METALARM 3500 series Manual

Metalarm™Series 3500 Metal Detectors
Installation, Operation
and Maintenance
Instructions
ERIEZ MAGNETICS HEADQUARTERS: 2200 ASBURY ROAD, ERIE, PA 16506–1402 U.S.A.
WORLD AUTHORITY IN SEPARATION TECHNOLOGIES
MM-246A
METALARM™
SERIES 3500
METAL
DETECTORS

2
Introduction
Careful attention to the following requirements will assure the most
efficient and dependable performance of this equipment.
If there are any questions or comments about the manual, please call
Eriez at 814/835-6000 for metal detection assistance.
©2011 ERIEZ MAGNETICS ALL RIGHTS RESERVED
CAUTION
Safety labels must be affixed to this product. Should
the safety label(s) be damaged, dislodged or removed,
contact Eriez for replacement.
CAUTION
Metal Detectors emit electromagnetic fields. Contact
the American Conference of Governmental Industrial
Hygienists, Cincinnati, Ohio, U.S.A. (www.acgih.org)
for additional information.
CAUTION
If you use a medical implant or similar device, you
must never approach the equipment because your
device may malfunction in the electromagnetic field,
with consequences up to and including death.

Metalarm™Series 3500 Metal Detectors
3
Table of Contents
METALARM™3500 AND 3500CE METAL DETECTOR SYSTEM
DESCRIPTION........................................................5
INSTALLATION .......................................................6
Control Unit Mounting.........................................6
Search coil Mounting..........................................6
Flat Coil (Model TR) ...........................................6
Idler Conveyors (Models TR & BR)
TR10 Tpe Search Coil .......................................7
Idler Conveyors
Bridge Coil (Model BR).......................................8
Vibrator or Belt Conveyors (Model VC)
Vibratory Trough Coil (Model VC) ....................10
Plate Coil (Model PL) .......................................11
Installation Recommendations .........................11
for Connecting RFI Filters to
High Frequency Inverters
Bag Dropper.....................................................12
ELECTRICAL CONNECTIONS.............................14
Power Supply ..................................................14
Control Relay Contacts ...................................15
Fuse .................................................................15
Sensor Coil Connections .................................15
OPERATING INSTRUCTIONS............................. 18
Indicator Lights ............................................... 19
Sensitivity Adjustment .................................... 19
Signal Level Indicator ..................................... 19
REPAIRS AND ADJUSTMENTS ..................... 20
Electronic Board Mounted Switches................ 20
Wiring to the Conveyor Motor Starter.............. 21
Auxiliary Relay ............................................... 22
Auxiliary Relay Wiring ..................................... 23
TROUBLESHOOTING ......................................... 23
Suggestions for Troubleshooting
Environmental Interference............................. 23
Movement of Metal ......................................... 23
Intermittent Loops of metal
surrounding the Sensor................................... 24
Excessive line voltage fluctuations ................. 24
Proximity of severe
RF radiation sources....................................... 25
PARTS LIST ......................................................... 26

4
Important Information
From Eriez
This information is provided to assemblers and
electricians due to the importance of proper methods
for wiring of controls. These methods are revised
and updated from time to time as Eriez perceives
necessary. This information covers distances from
various categories of cables and Eriez Metal Detector
wiring standards. The cable categories are:
1. AC Power cables
2. DC Distribution (thermocouple, power supplies)
3. Signal and Logic
3a. Analog (low level)
3b. Digital logic
Category 1 cables are to be routed along frame
members and panels. Avoid open space hanging.
Category 2 cables are routed as 1 but separate from 1.
Category 3 cables are routed separately from 1 and 2.
Category 3b are to be spaced 2.5 cm (1") from
Category 1 for each meter of run.
Category 3a cables are to be spaced 25 cm (10") from
category 1 for each meter of run.
Use separate machine entry holes for categories 1, 2
and 3 cables.
When Eriez Metal Detectors are being installed in
plants using VFC drives, the following precautions
are recommended:
1. Route VFC wiring and Eriez Metal Detector wiring
into separate metallic conduits.
2. Separate power sources should be used for VFC
drives and Eriez Metal Detectors.
3. The use of a Harmonic Neutralized Constant
Voltage Transformer for the Eriez Metal Detector
power is recommended. Use separate conduits
for in and out wiring.
4. Twist AC common circuit run wires together to
minimize electromagnetic field interference.
5. Follow cable category separations as
detailed above.

Metalarm™Series 3500 Metal Detectors
5
The Metalarm™3500 and 3500-CE Metal Detector
consists of a control unit, one or more sensor coils
dependent upon the application, and optional
accessories such as the sack dropper.
Description
FIGURE 1
Control unit dimensions

6
CONTROL UNIT MOUNTING
The Metalarm 3500 control unit is supplied with four
mounting brackets for wall mounting. The dimensions
are shown in Figure 1.
Ideally the control unit should be mounted within 10-15'
(3-5 m) of the sensor coil unit and no more than
66' (20 m).
The control unit must be mounted in a location with
low amounts of vibration, if the area exhibits a high
level of vibration, independent mounting of the control
enclosure must be implemented. Shock mounts for the
control enclosure may be another consideration, based
on the severity of the installation.
The Metalarm 3500 control unit will normally be
mounted by means of four 5/16 inch or M8 bolts
utilizing the four mounting holes.
Adequate clearance must be allowed below the control
unit enclosure to allow for cable entry and exit.
NOTE: Do not replace the HDPE mounting bars, as
these are provided to electrically isolate the control
unit from the metal conveyor framework. Similarly no
metal work should be in contact with the metal control
unit case after mounting on the conveyor.
Failure to comply with the above mounting procedures
will invalidate the ‘CE’ certificate covering the
EMC regulations.
SEARCH COIL MOUNTING
The following instructions give details of how to install
the various types of standard search coils supplied as
part of the Metalarm Metal Detector.
The search coil should be assembled using the
instructions supplied with the search coil.
UNDERBELT COIL (MODEL TR) ‑
IDLER CONVEYORS
Locate a suitable position in the conveyor mid way
between two idlers where:
• There will not be a return idler or cross piece
beneath the search coil.
• There is not a joint in the conveyor frame.
Installation • Metal, when detected, can easily be removed from
the conveyor belt.
• There is no moving metal in the vicinity.
• Any metal base plate present can be removed or
replaced by non-metallic material.
• Any metal covers over the belt can be removed or
replaced by non-metallic material.
Place the search coil on the conveyor frame at the
chosen position. There should be at least a 1' (25mm)
gap between the underside of the conveyor belt and
the top of the search coil. If not cut out notches in the
bottom of the search coil at all four corners so as to
lower the search coil within the conveyor frame.
User supplied stainless steel “L” brackets are
suggested for securing the search coil assembly to the
conveyor. Brackets should be fitted to the coil, in the
area marked for such purposes, as shown on the coil
assembly drawing. (See Figure 2)
The search coil should then be bolted to the conveyor
frame with the coil electrical connection on the
opposite side of the conveyor frame to any heavy-duty
cables or wiring.
A recommended idler spacing of 48"- 60" should apply
to the infeed and outfeed idlers adjacent to the search
coil. An idler isolation kit is recommended and may
be purchased from the factory. The idler isolation kit
provides suitable materials to electrically insulate the
idlers from the conveyor frame. Insulating the idlers
directly adjacent to each side of the search coil will help
to alleviate any possible false tripping. Electrical loops
can be created from the metal detectors field in relation
to the surrounding metal. The idlers on each side of
the search coil should be checked to see that all nuts
and bolts have been securely tightened.
The cable connecting the search coil to the control
unit should then be attached to the connector on the
underside of the search coil and to the control unit. The
cable should be secured and protected from damage.

Metalarm™Series 3500 Metal Detectors
7
The search coil coax cable must not cross directly
under the search coil, as this may cause false tripping
to occur. The cable should be replaced should any
nicks in its outer cover occur.
If standard metal conduit must be used to protect the
search coil, separate conduits must be used for each
cable; receiver and transmitter. If a clip detector is
required, the cable may be run in the same conduit as
the receiver or transmitter coil.
TR10 TYPE SEARCH COIL ‑ IDLER CONVEYORS
Locate a suitable position in the conveyor mid way
between two idler sets where:
• There will not be a return idler or cross piece
beneath the search coil.
• There is not a joint in the conveyor frame.
• Metal when detected can easily be removed from
the conveyor belt.
• There is no moving metal in the vicinity.
• Any metal base plate present can be removed or
replaced by non metallic material.
• Any metal overbelt covers can be removed
or replaced.
Place the search coil on the conveyor frame at the
chosen position. There should be at least a 1" (25mm)
gap between the underneath of the conveyor belt and
the top of the search coil. If not cut out notches in the
bottom of the search coil at all four corners so as to
lower the search coil within the conveyor frame.
FIGURE 2
Coil assembly

8
Installation (cont.) BRIDGE TYPE (MODEL BR) SEARCH COIL ‑
IDLER CONVEYORS
Locate a suitable position in the conveyor mid way
between two idler sets where:
• There will not be a return idler or cross piece
beneath the search coil.
• There is not a joint in the conveyor frame
• Metal, when detected, can easily be removed from
the conveyor belt
• There is no moving metal in the vicinity
• Any metal base plate present can be removed or
replaced by non-metallic material.
• Any metal overbelt covers can be removed or
replaced by non metallic material
Place the search coil on the conveyor frame at the
chosen position. There should be at least a 1" (25mm)
gap between the underside of the conveyor belt and
the top of the search coil. If not cut out notches in the
bottom of the search coil at all four corners so as to
lower the search coil within the conveyor frame.
FIGURE 3
Brackets (not supplied) to hold the search coil to the
conveyor frame should be fitted to the coil on the side
supports shown in Figure 3.
The search coil should then be bolted to the
conveyor frame.
Fit top search coil section and bolt down.
The pair of idlers adjacent to either side of the search
coil should be checked to see that all nuts and bolts
have been tightened down firmly. Preferably the idler
frames should also be spot welded once at each of the
four corners to the conveyor frame.
This type of coil configuration is designed for transmit/
receive mode operation only and both coils are
connected directly to the control unit. See Electrical
Connection: Sensor Coil Connections and Figure 3.
Remember to make sure the cables are tied to the
conveyor frame to prevent them from being damaged.

Metalarm™Series 3500 Metal Detectors
9
FIGURE 4
User supplied stainless steel “L” brackets are
suggested for securing the search coil assembly to
the conveyor. Brackets should be fitted to the coil. The
area for this purpose is shown on the coil assembly
drawing. (See Figure 4)
The search coil should then be bolted to the conveyor
frame so that the coil socket is on the opposite side of
the conveyor frame from any heavy-duty cables
or wiring.
Fit the top search coil section and bolt it in place.
A recommended idler spacing of 48"- 60" should apply
to the infeed and outfeed idlers adjacent to the search
coil. An idler isolation kit is recommended and may
be purchased from the factory. The idler isolation kit
provides suitable materials to electrically insulate the
idlers from the conveyor frame. Insulating the idlers
directly adjacent to each side of the search coil will help
to alleviate any possible false tripping. Electrical loops
can be created from the metal detectors field in relation
to the surrounding metal. The idlers, either side of the
search coil, should be checked to see that all nuts and
bolts are tight.
In the case of series connection, connect the lower
coil using the short length of cable provided to the
unmarked socket on the top coil. The cable to connect
the search coil to the control unit should be connected
to the socket marked ‘CU’ on the top search coil. In
the case of transmit/receive mode operation, both coils
are connected directly to the control unit.
In both cases make sure the cables are secured to the
conveyor frame and protected to prevent them
being damaged.
The search coil coax cable must not cross directly
under the search coil, as this may cause false tripping
to occur. The cable should be replaced should any
nicks in its outer cover occur.
If standard metal conduit must be used be used to
protect the coil cable(s), separate conduits must be
used for each cable; receiver and transmitter. If a clip
detector is required, the cable may be run in the same
conduit as the receiver or transmitter coil.

10
MODEL VC “U” SECTION BELT CONVEYORS OR
VIBRATOR CONVEYORS ‑ SEARCH COILS
Locate a suitable position in the conveyor where there
is going to be no metal within approximately 20"
(500mm) of the underside of the search coil when it
is mounted onto the conveyor. There should be no
moving metal in close proximity to the search coil.
In the case of vibratory conveyor the coil is usually
located midway between two of the vertical supports.
Cross braces under the search coil should be cut and
moved. To install a trough coil, it is necessary to cut
out a length of the base and part of the side walls of
the conveyor. (See Figure 5).
The exact dimensions of the required cut out will be
shown on the search coil assembly drawings supplied
with the search coil.
Draw a line 1" (25mm) from the edge of the cut out.
Along this line drill 5/16" dia (M8) holes at 4" (100mm)
spacing or longer depending upon the weight and
width of the search coil. Countersink the holes from
the inside of the conveyor.
Locate the search coil into the cut out and clamp it in
position. Using the holes in the conveyor as a guide,
drill through side and base of the search coil.
Bolt the search coil into position using countersunk
5/16" (M8) bolts x 1-1/2" (40mm) long and shakeproof
lock washers.
The cable from the search coil to the control unit
should be connected into the underside of the search
coil. The cable should be secured and protected
from damage.
The search coil coax cable must not cross directly
under the search coil, as this may cause false tripping
to occur. The cable should be replaced should any
nicks in its outer cover occur.
If standard metal conduit must be used to protect the
coil cable(s), separate conduits must be used for each
cable; receiver and transmitter. If a clip detector is
required, the cable may be run in the same conduit as
the receiver or transmitter
Installation (cont.)
FIGURE 5