Veeder-Root 7671 Series Technical Manual

DESCRIPTION
These instructions are for installation of the Series 7671 Solid
State Pulse Transmitter (see Figure 1) designed and
manufactured by Veeder-root Company, 2709 Route 764,
Duncansville, PA 16635, (814) 695-4476.
When a vertical bar appears adjacent to text or illustrations,
information has been added or changed at the last issue date.
These solid state pulse transmitters provide fast and accurate
signaling for remote indication totalizing and data monitoring
systems. They are cULus listed for gasoline pump computers
and applications that require monitoring of output shaft
rotation in hazardous locations.
The output can be either dual channel with 50 pulses per
revolution per channel or single channel with 100 pulses per
revolution. The dual channel pulse trains can be staggered or
overlapping. A staggered output allows errors to be detected
on either channel or on both concurrently (power loss to
pulser). An overlapping (quadrature) output permits the
detection of direction of rotation and errors on either channel
but not on both concurrently. The single channel devices are
used when greater pulse density is desired and error
detection is not required.
SPECIFICATIONS
Specifications listed are standard unless otherwise noted.
Optional features are available at additional cost.
Recommended Operating Conditions (each channel):
• Power Requirement: 10 to 15 VDC, 50 mA (max.) at 15
VDC
• Output Voltage: Dependent on load. (see Figure 2).
• Switching Times: Rise Time - 2 microseconds maximum
with 10 mA resistive load to ground; Fall Time - 4 micro-
seconds maximum.
Rotation: Standard is bidirectional. Optional models
available with no-back feature.
Input Shaft Speed: 600 rpm maximum
Torque: 2 0z-in. maximum (144 g-cm)
Output Pulse: Dual channel at 50 ppr, staggered or
overlapping (quadrature). Single channel at 100 ppr (See
Figure 3).
Duty Cycle:
• Overlapping/Quadrature: 50% ±10% high/low ratio.
Second channel phase displaced by 90° ±18°.
• Staggered: 75% ±5% high/low ratio. Second channel
displaced by 180° ±18°.
• Single Channel: 50% ±10% high/low ratio.
Manual No. 230194, Rev C, April 2025
SERIES 7671
PULSE TRANSMITTER
Manual No. 230194, Rev C, April 2025
.75 VOLTS - AMPERES MAX. NON INDUCTIVE
929A
MAX
RPM
CAUTION
DISCONNECT THE DEVICE FROM THE SUPPLY CIRCUIT BEFORE
OPENING. KEEP ASSEMBLY TIGHTLY CLOSED WHEN IN OPERATION.
ATTENTION
CIRCUIT AVANT D'ENLEVER LE COUVERCLE, GARDER
Figure 1. Series 7671 Pulse Transmitter
Circuit Class: For National Electric Code Class 2 Circuits
only
Operating Environment: -40° to +82°C (-40° to +180°F)
Storage Environment: -55° to +125°C (-67° to +257 °F)
Shaft: Specify length of either 24.28 or 41.80 mm (0.956 or
1.672 inch). Other lengths available.
Shock: Normal shipping.
Housing: Explosion-proof. For use in hazardous location,
Class 1, Group D.
Mounting: Three .250-20 UNC-2B blind tapped holes,
spaced 120° apart on a 63.5 mm (2.5 in.) diameter bolt circle.
Leads: 48 in. (120 cm) of 3 or 4 conductors and ground, gas
and oil resistant, #18 AWG wire.
C o n s u l t Ve e d e r - R o o t o n a n y u n u s u a l
a p p l i c a t i o n , i n s t a l l a t i o n , o r p o s s i b l e
modification of this basic design.
Voltage/Current
16
14
12
10
Output
8
Voltage
6
in VDC
4
2
0
Low Output - .25 V Max.
Figure 2. Output Current
Technical Manual
5-001
Issued: 04/2025
Supersedes: 3/93
PULSE
TRANSMITTER
FORM NO.
UP TO .05 AMPERES - UP TO 15 VOLTS DC
NEC CLASS 2 CKTS ONLY
T E L E M E T E R I N G
SER.
EQUIPMENT FOR USE IN
HAZARDOUS LOCATIONS NO.
CONDUIT SEAL
600
NOT REQUIRED
TO PREVENT IGNITION OF HAZ. ATM..
OUVRIR LE
LE COUVERCLE BIEN FERME LORSQUE
LES CIRCUITS SONT
SOUS TENSION
HIGH OUTPUT LOAD LINE
15 VDC Supply
10 VDC Supply
10 20
Output Current in mA
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