AMETEK 955S Smart Brik LDT User Manual

INSTALLATION MANUAL

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955S BRIK

Smart BRIK LDT

955 Series

Series 956

ABSOLUTE PROCESS CONTROL
KNOW WHERE YOU ARE... REGARDLESS

1080 N. Crooks Road, Clawson, MI 48017-1097 Phone [phone]
Toll Free 800-635-0289 Fax [phone] www.AMETEKAPT.com

Introduction

The 955S Smart Brik is an accurate programmable,
auto-tuning, non-contact, linear displacement transducer

in an economical, low prole package. The transducer
utilizes our eld proven magnetostrictive technology

to give absolute position, repeatable to .01% of the
programmable sensing distance. The streamlined
anodized aluminum extrusion houses the sensing element
and electronics. The magnet moves over the sensing
element that determines the position and converts it to an
analog output. It can be ordered with various outputs:

0 to 10 VDC

-10 to 10 VDC
0 to 5 VDC

-5 to 5 VDC
4 to 20mA

The 955S Smart Brik has a few truly unique features. The

rst one being the LDT’s auto-tuning capability, the ability

to sense a magnet other than the standard slide magnet
and adjust its signal strength accordingly. Another feature
is the analog output is programmable over the entire
active stroke length. The active stroke area of the LDT lies
between the Null Zone and Dead Band.

Mounting

The transducer can be mounted vertically or horizontally
using SD0522000 Mounting Brackets. The mounting
brackets slide in the grooves on the lower part of
the extrusion and clamp down when tightened. It is
recommended to use one mounting bracket on each end
and every three feet between.

NOTE: If using the oating magnet option, you must

set the automatic gain control.

Ferro-magnetic material, (material readily magnetized)
should be placed no closer than .25” from the sensing
surface of the LDT.

LED Colors

Green: Magnet is present and within the active
programmed range.
Red: Fault, the LDT has lost its signal from the magnet or
the magnet has moved into the Null Zone or Dead Band.
Yellow: Magnet is out of the programmed ZERO to SPAN
range.

Setting Zero & Span Positions

There is a diagnostic LED located at the connector end of
the probe that remains green while a good magnet signal
is present and when the magnet is in the programmed
stroke area. The LED turns yellow when the magnet is
out of the programmed active range, but still within the
active stroke area. The LED turns red and the output
goes to 0 volts on voltage output units, or 4mA on current
output units when there is no magnet present or when the
magnet is out of the sensing area. The unit can easily be

changed in the eld.

From To

0 to 10 VDC 10 to 0 VDC

-10 to 10 VDC 10 to -10 VDC

0 to 5 VDC 5 to 0 VDC

-5 to 5 VDC 5 to -5 VDC

4 to 20mA 20 to 4mA

NOTE 1: As an added benet, the 955S is FM approved

for Class I, Div II, Groups A, B, C, D applications when
installed and wired per drawing E0241100.
NOTE 2: If your application does not require FM Class I,
Div II approval, wire the 955S using a standard 4 pin Euro
cordset from Ametek or others.

The Series 955S is programmable over the entire active
stroke length of the LDT. Keep in mind that there is a
3” Null area at the connector end of the LDT and a 1.5”
Dead area at the other end of the LDT that the magnet
must stay out of at all times. The diagnostic LED can
help aid you in the setup of the Zero and Span. A green
or yellow LED means that it is OK to program the LDT
in this area, a red LED means that the LDT cannot be
programmed in this area.

To set the ZERO and SPAN position for the probe follow
these steps:

1. Power up the probe in normal operating mode (i.e.

“PRGM” pin oating)

2. Place magnet assembly where ZERO is to be located,
but within the active region of probe

3. Momentarily short “PRGM” pin (pin 2) to ground (pin 3)

4. Place magnet assembly where SPAN is to be located,
but within the active region of the probe

5. Momentarily short “PRGM” pin (pin 2) to V+ (pin 1)

NOTE 1: AGC should be set rst before setting the
ZERO and SPAN positions when using a oating magnet.
NOTE 2: SPAN could also be set rst, followed by setting

the ZERO position.

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1080 N. Crooks Road • Clawson, MI 48017 • 800.635.0289 • 248.435.0700 • Fax [phone] • www.AMETEKAPT.com

NOTE 3: ZERO or SPAN can be adjusted individually
without setting the other.
NOTE 4: ZERO = 0V on 0 to 10 VDC units and 4mA on 4
to 20mA units.

For your convenience, Ametek offers an in-line
programming unit (955-1409) that can be installed in­line with the LDT. The in-line programmer uses a rocker
switch to program the zero and span. For details, see
accessories on page 7.

Automatic Gain Control

To place the probe back into the normal operating mode
follow these steps:

1. Power down the probe

2. Remove short from “PRGM” pin

3. Apply power to the probe

The probe is now in the normal operating mode.

NOTE: The north pole of the magnet should be pointed
towards the probe.

The Automatic Gain Control feature is only used when
sensing a magnet other then the standard SD0521800
slide magnet. If you are using the standard slide magnet
skip to Setting Zero and Span Position.

When using the Floating Magnet assembly (SD0522100),
the magnet should be installed within 3/8” of the sensing
surface. The magnet assembly should also be installed
in such a manner that it remains an even distance from
the aluminum extrusion throughout the entire stroke.
Improperly installed magnets can result in output signal
non-linearity.

To set the Automatic Gain Control (AGC) level for the
probe follow these steps:

1. Place magnet assembly close to the Dead Band (but
within the active region) of the probe

2. Power down the probe

3. Short “PRGM” pin (pin 2) to ground (pin 3)

4. Apply power to probe

A. The LED ashes RED indicating it is in the AGC

mode.

B. The LED will change to ashing GREEN when it

has determined the proper AGC level and has
saved it to non-volatile memory.

NOTE: When the probe is in AGC mode, the output will
be at either 0 volts or 4mA, depending on the model that
was ordered.

The AGC is now complete.

Specications

Input Voltage 10 to 30 VDC
Current Draw

Voltage Units

Current Units

Output 0 to 10 VDC

Linearity +/- 0.05% of Stroke or +/- 0.028” whichever is

Accuracy +/- 0.1% of Stroke or +/- 0.050” whichever is

Repeatability +/- 0.01% of Full Stroke or +/- 0.014” whichever

Update Time
Stroke Length:
4” ≤ 50”
51” ≥ 100”
101” ≥ 150”
151” ≥ 180”

Operating Temperature -20° to 70° C
Span Length 4” to 180”
Null Zone 3.00”
Dead Band 1.50”
LED Green = Power is applied and magnet is present

Connector Standard 4 Pin Micro

Approvals CE

Enclosure IP67, IP68 Optional
Output Load

Voltage Output
Current Output

Specications are subject to change without notice.

Specications are based on a typical 36” LDT.

80mA @ 10 VDC
35mA @ 30 VDC
90mA @ 10 VDC
55mA @ 30 VDC

10 to 0 VDC

-10 to 10 VDC
10 to -10 VDC

greater

greater

is greater

1ms with 5ms settling time
2ms with 4ms settling time
3ms with 3ms settling time
4ms with 4ms settling time

Red = Fault, magnet is in the Dead Band or lost
Yellow = Out of the active programmed range

12mm Euro Connector

FM - When installed per drawing E0241100

1KΩ (1.5KΩ for +/- 10V) (minimum)
(Vin - 4) / 20mA (maximum)

-5 to 5 VDC
5 to -5 VDC
0 to 5 VDC
5 to 0 VDC
4 to 20mA
20 to 4mA

1080 N. Crooks Road • Clawson, MI 48017 • 800.635.0289 • 248.435.0700 • Fax [phone] • www.AMETEKAPT.com

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