1
DESCRIPTION & SPECIFICATIONS
DESCRIPTION:
The OMEGA DPF70 is a dual input (channel A and B) counter/
ratemeter, each with its own 5 digit dividing scale factor. The two 5
AMP preset relay outputs can be programmed by the user to apply
to the "A" total counter, the "A" ratemeter, or the "B" counter or the
net total of A and B inputs. The user can view the Net Total of
"A+B", the Net Total of "A-B", the rate of A, or A and B counters
separately. The "DPF75" version shows rate and total (as de-
scribed above). The "DPF76" is exclusively a counter and the
"DPF78" is exclusively a ratemeter.
SPECIFICATIONS:
DISPLAY
6 digit, 0.55" High LED
INPUT POWER:
110 VAC
±
15% or 11 to 15 VDC
220 VAC
±
15% or 11 to 15 VDC
CURRENT:
250 mA DC max. or 6.5 VA AC
OUTPUT POWER
(AC powered units only)
+12 VDC @ 50 mA, unregulated -10 + 50%
TEMPERATURE:
Operating: +32
°
F (0
°
C) to +130 F (+54
°
C)
Storage: -40 F (-40
°
C) to +200
°
F (93
°
C)
DIMENSIONS:
See next page.
WEIGHT:
2 Lbs. (1 kg)
MEMORY
EEPROM stores data for 10 years if power is lost.
INPUTS:
3:
High Impedance DC pulse input Open or 0-1 VDC
(low), 4-30 VDC (high), 10 KOhm imp. 10 KHz max.
speed. Accepts simultaneous inputs.
3M:
Mag. Input, Input A only, accepts 30mV input (50 V max. P/P)
signals 10 KOhm imp. 5 KHz max. (Input B, 4-30V)
3MB: Mag. Input, Inputs A & B, accepts 30mV input (50 V max. P/P)
signals 10 KOhm imp. 5 KHz max.
5:
4-30 V Count pulses on Input A, 4-30 V Direction
Control input (level) on Input B.
5M:
30 mV Count pulses on Input A (50 V max. P/P)
4-30 V Direction Control input (level) on Input B
9:
Quadrature, accepts 4-30 V pulses with 90
°
phase
shift for direction detection.
9MB: Quadrature, accepts 30 mV (50 V max. P/P) pulses with
90
°
phase shift for direction detection.
NOTE:
The Mag. inputs have filtering as follows: up to 300hz
@30mV, 5KHz @ .25V to 50V max.
RESET:
Front Panel:
Resets displayed value and control output
Remote:
4-30 VDC negative edge resets COUNTER "A" and control
output
K FACTOR/SCALING
In the standard unit a fixed K-Factor is used to convert the input
pulses to engineering units. The 5 digit K-Factor dividers, with
decimal keyed into any position, allow easy direct entry of any K-
Factor from 0.0001 to 99999. Separate factors may be entered for
the 2 separate input channels.
CONTROL OUTPUTS:
Relays:
2 each N.O. Relay; 5 Amps120/240 VAC or 28 VDC.
(N.C. relay contacts and NPN transistor output
available with solder jumpers. Transistor output is
internally pulled up to 10 VDC through relay coil, sinks
from 10 VDC to .5 V @ 100 mA)
Analog Output:
An optional 4-20mA (0-20mA) output is available for
the DPF70 series. The output can be programmed
to track rate or total. This feature is available by
adding suffix A to the part number. Connections are
via a 2 terminal pluggable screw connector.
Programming is accomplished by using the front panel
in conjunction with rear dip switches.
Accuracy: 50uA worst case.
Compliance Voltage: 3 to 30 VDC non inductive.
RS232/RS422SERIAL INTERFACE
If the serial interface option is supplied, up to 99 units can be linked
together. (The terminal addressing the unit must be capable of
driving all loads in the loop.) Unit status and new set points can be
communicated by serial communication. Mode changes, however,
must always be made on the front panel. Data is transmitted at
selected baud rates using standard seven bit ASCII characters and
parity with two additional bits of “Start” and “Stop” to make up the
standard ten bit character.
Data is received and transmitted over standard EIA RS232 or
RS422 levels. Each 10 bit character is made up of a start bit, 7 bit
ASCII code, parity bit and stop bit. Unit number, baud rate and
parity are entered in the “Program Setting” set up mode and remain
in memory even if power is off.
Note that the input impedance of RS232 is 3K or 7K Ohm worst
case. The terminal addressing the unit must be capable of driving
all loads in the loop. RS422 input impedance is much higher and
there is usually no problem driving 25 units. Unit serial transmit line
remains in a high impedance “OFF” state until addressed.
PRESETS
Two control outputs are provided. To set relay values, press “menu”
button until “Relay” appears on the display, the A and B outputs
can be assigned to the ratemeter (high/low), one preset for rate
and one for total, or two presets (2 stage shut off) on the A and B
counters. A 5 digit value can be entered for both presets and the
decimal point location is the same as the counter. The outputs can
be set to energize from 0.1 to 99.9 seconds or latch (0.0). If a value
other than 0.0 is entered, the counters will auto reset at the preset .
In the A-B or A+B versions, the relays will be assigned to either net
total or A rate.
LOCKOUT
Unauthorized front panel changes can be prevented by entering a
user selected 5 digit code, in the “LOC” , . mode. The front panel
can be completely locked out or the presets can remain accessible.
RATEMETER
Accurate to 4 1/2 digits (
±
1 display digit). The rate meter can be
programmed to accept almost any number of pulses per unit of
measurement, sample from 2 to 24 seconds maximum, and auto-
range up to 5 digits of significant information. In the “RPS” mode,
the ratemeter displays in units per second, and in the “scale” mode,
units per hour or per minute. The unit will display the rate of the A
Input only.
COUNTER
The two 6-digit counters can count at 10Khz speed. Each can
have a 5-digit dividing scale factor. The counter advances on the
positive edge of each pulse. Count up or down modes available, as
are quadrature inputs from encoders for position or length mea-
surement. The unit can be programmed to view the net value of
"A+B" or "A-B", or A and B as separate counters.
