Warner Electric A30 User Manual

A30 Single Range Tensioncells

P-2012-3
819-0403

Installation Instructions

Contents

General Information . . . . . . . . . . . . . . . . . . . 3

Installation and Operation . . . . . . . . . . . . . . . 6

Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . 8

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . 9

Recalibration . . . . . . . . . . . . . . . . . . . . . . . 10

Dimension Drawing . . . . . . . . . . . . . . . . . . 11

Warranty . . . . . . . . . . . . . . . . . . . . . Back Page

Failure to follow these
instructions may result in product damage,
equipment damage, and serious or fatal
injury to personnel.

Warner Electric • 800-825-9050 P-2012-3

2

Description

Damper

C-Flexure
Far Side

Mechanical Stop

Load
Plate

LVDT
LVDT

Core

A. General Information

Warner Electric Series 30 Type A Tensioncells
are force transducers, specially designed to
measure and control tension on single strand
wire, cable or filaments, on continuous strip pro­cessing lines. They convert the mechanical
force of strand tension into an electrical signal,
which is directly proportional to the strand ten­sion.

Type "A" Tensioncells are installed as single
units with a pulley or sheave (See Figures 1a
and Figure 1b). They are intended for NON­ROTATING shaft installations. Tensioncells can
be provided to accept shaft sizes from 3/4 inch
to 1-7/16 inch. (See Table 1-B, Page 11)

B. The Mechanical System

The mechanical system consists of a Patented
"C-Flexure Pivot Assembly" which incorporates
a mounting Base Block, frictionless elastic pivot
(or hinge), and Load Plate. (See Figure 2) When
a mechanical force is applied to the Load Plate,
the pivot permits its deflection toward or away
from the Base Block.

For our discussion here, deflection of the Load
Plate toward the Base Block is defined as the
"Compression Mode", while the opposite is
defined as the "Tension Mode". Tensioncells are
designed to operate equally well in either mode.

The Base Block contains an integral Mechanical
Stop to limit the amount of deflection in either
direction, and a Viscous Damper to allow control
of the tensioncell response to rapid changes in
apparent tension loads. (See Figure 2)

W1

Figure 1a Figure 1b

W1

Figure 2

Warner Electric • 800-825-9050 P-2012-3

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C. The Electrical System

Black - (2)
Red + (1)

Green (3)
Blue (4)

Input

Output

X Twisted Leads

A B

Oscillator Demodulator

P1

S1

S2

X

X

WhenSupplied

withCable

(1)Red +DC
(2)Black –DC

(3)Green –Signal
(4)White +Signal

CD

BAC

D

7

6

5

4

3

2

1

0

.030” 0.0 .030”

3.5 V. Set Point

Tension

Compression

LVDT Output vs Deflection

O

u

t
p
u

t

V

o

l

t
a
g
e

Deflection

The electrical system consists of a Linear
Variable Differential Transformer (LVDT) which
converts the mechanical deflection of the Load
Plate into a useful electrical output signal. (See
Figure 3) The moveable core of the LVDT is
mechanically coupled to the Load Plate.
This core assemble is factory set and is not
accessible.

D. Type "K" DC LVDT

As illustrated in Figure 3, a DC LVDT consists of
the following components:

• An oscillator network, which converts the DC
input voltage into a high frequency alternat­ing current for exciting the primary coil (P1)

• A Primary Coil (P1)

• A movable, permeable metallic core

• Two Secondary Coils (S1 and S2)

• A demodulator and summing network to rec­tify and integrate the currents from the
Secondary Coils

With Warner Electric LVDTs, the input and out­p

ut circuits are electrically isolated from each
other and from the mechanical structure of the
tensioncell. Thus, they may be used in "floating
ground" or "ground return" systems. This elimi­nates the need for extra circuit boards which are
required for most straingage loadcells.

Tensioncells are factory adjusted to provide an
offset voltage with no load applied (no deflec­tion). Using an input of 24 volts DC, the LVDT is
set to provide an output of 3.5 volts into a resis­tive load of not less than 100,000 ohms. The
voltage resulting from the maximum rated
deflection then adds to or subtracts from the 3.5
volt offset. This results in an output voltage of

3.5 to 6.5 volts in the Compression Mode and

3.5 to 0.5 volts in the Tension Mode. (See
Figure 4)

While acceptable performance may be obtained
over an input voltage range of 6.0 to 30.0 volts
DC, the output voltage will vary in direct propor­tion to the input voltage. Because of this, the
use of a well regulated constant voltage power
supply is essential for accurate and repeatable
tension measurement.

Warner Electric • 800-825-9050 P-2012-3

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Figure 3

LVDT Output vs. Deflection Chart

Figure 4