Sensotec HH User manual
Model HH
Signal-Conditioner / Indicator
2080 Arlin
g
ate Lane, Columbus, Ohio 43228 USA • (614)850-5000
Sensotec, Inc.
2080 Arlingate Lane
Columbus, Ohio 43228 USA
Copyright © 2002 by Sensotec, Inc. all rights reserved
Telephone: (614)850-5000
FAX: (614)850-1111
Toll Free: 1-800-848-6564
E-mail: service@sensotec.com
WWW: http://www.sensotec.com
Model HH Instruction Manual
Document Part Number: 008-0139-00
Rev. B: March, 2003
IMPORTANT! IT IS RECOMMENDED THAT YOU READ
THIS DOCUMENT THOROUGHLY BEFORE APPLYING
POWER TO THIS UNIT. THIS DOCUMENT CONTAINS
INFORMATION ON WIRING, CALIBRATION, AND USE
OF FEATURES.
Sensotec continually improves its products, and thus the
information herein is subject to change without notice.
Chapter 1
INTRODUCTION
1.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.2 Specifications . . . . . . . . . . . . . . . . . . . . . 6
1.3 Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Chapter 2
SETUP
2.1 Initial Setup . . . . . . . . . . . . . . . . . . . . . . . 11
2.2 Transducer Hookup. . . . . . . . . . . . . . . . . 12
2.3 Calibration. . . . . . . . . . . . . . . . . . . . . . . . 13
WARRANTY 15
Model HH Instruction Manual pa
g
e 5
Chapter 1
INTRODUCTION
1.1 Overview
The Sensotec Model HH is a complete hand-held portable
signal-conditioner/indicator for use with strain-gage trans-
ducers. The instrument provides an excitation power sup-
ply for such transducers, amplifies the transducer’s
output, and indicates this reading in engineering units. It
can indicate this reading in a continuous fashion (tracking
mode) or display only the highest reading (peak mode)
using a switch to make the selection.
Other features of the instrument include:
•3-1/2 digit liquid-crystal display
•use of a standard, 9-volt battery
•low-battery warning indication
Though the instrument is small, it is a full signal-condi-
tioner, providing adjustment for zero, span, scaling and
switch-selected gain. It is usable with a wide variety of
strain-gage transducer types, and is the ideal instrument
for the those who must travel and take readings from a
wide variety of transducers.
pa
g
e 6 INTRODUCTION
1.2 Specifications
SIGNAL CONDITIONER
Excitation Volta
g
e to transducer: 2.46 VDC
Minimum Transducer Impedance: 120 ohms
Input Si
g
nal Sensitivity for Full-Scale
Indication:
0.5 to 8.0 mV/V
Peak Detector Bleed-Off Rate < 0.01% per second
DISPLAY
Type: 3½LCD, plus
optional dummy zero
Low-Battery Indicator: yes
Over-Ran
g
e Indicator blinkin
g
di
g
its
Di
g
it Hei
g
ht: 0.5”
Conversion Rate: 3 readin
g
s / second
PHYSICAL
Size: 3.6”W x 6.75”L x 1.75”H
Enclosure Material: ABS impact-resistant plastic
Transducer Connector: four bindin
g
posts capable of spade
lu
g
s, banana plu
g
s, alli
g
ator clips and
stranded or solid wire
Power Supply: 9-volt battery (NEDA 1604)
Battery Life: 15 hours minimum with 350-ohms
transducer impedance
Model HH Instruction Manual pa
g
e 7
1.3 Layout
1.3.1 Front Panel Controls / Indicators
[ON/OFF] Switch
This switch controls power to the instrument from the bat-
tery.
[SHUNT CAL] Switch
This switch connects the instrument’s shunt calibration
resistor to the transducer and is used during setup. See
“SETUP”on page 11 for more information.
[PEAK/TRACK] Switch
This switch selects the mode of operation of the instru-
ment. In the TRACK mode, the instrument's display will
continuously follow the transducer reading. In the PEAK
position, the instrument will retain and display the value of
the most positive reading detected during operation. To
reset the peak, switch the [PEAK/TRACK] switch to the
TRACK position. (A slight decay of the peak value dis-
played over an extended period of time is normal).
[ZERO] Potentiometer
This control is used to obtain a zero indication, thus can-
celling drifts or offsets that could exist in the instrument or
transducer.
[SPAN] Potentiometer
This control adjusts the fine gain of the amplifier. It is
used to be certain that the reading obtained from any
transducer can be scaled to the proper level on the dis-
play.
“LO BAT” Indicator
This indication appears in the upper-left of the display and
indicates when the battery voltage is getting low.
Model HH Instruction Manual pa
g
e 9
1.3.2 Connection Terminals
On the top of the instrument are four binding-post connec-
tors for the transducer connections. Labels describe the
function of each of the terminals.
1.3.3 Battery Replacement
The access door for the battery is located on the rear of
the instrument. To replace the battery, slide this door in
the direction indicated by the arrow. When changing bat-
teries, remove the clip from the battery carefully, in order
to protect the wiring.
Table 1: Transducer Hookup
Instrument Transducer
+EX (+)Excitation
-EX (-)Excitation
+IN (+)Output
-IN (-)Output
Table of contents
