Omega Products RD3721-12 User Manual

1-4 Channel
Flatbed Pen Recorders

Accept DC Voltage, Thermocouple
and RTD Inputs

RD3700 Series

Starts at

$

1955

Shown with:
A) GKMQSS-125G-6 low-noise

thermocouple with 30°
connector, $27 (see page A-50)

B) PR-11-2-100-1/4-6-E RTD

probe, $66 (see page C-82)

C) OS36-K-240F infrared

thermocouple, $255
(see page J-47)

⻬ Accepts DC Voltage,

12 Types of
Thermocouples
and RTD Inputs

⻬ Choice of Measured

Data, Bar Graph
or Range Data
Display Modes

RD3722-42, $4704.

A

B

C

⻬ Model RD3721 Has

Printer and Electronic
Pen Lift

⻬ Alarm Outputs

of up to Four Points
(Optional )

S-45

⻬ Optional 256 K Memory

Card for Increased Data
Storage

⻬ Optional GPIB or

RS232C Interface

⻬ 250 mm (10") Chart
⻬ 115/230 Vac Powered

The easy-to-operate OMEGA

®

RD3721 and RD3722 flatbed pen
recorders are sophisticated, high
performance units which accept a
wide range of input types. Features
include a choice of measured data,
bar graph or range data display
modes. Versatile optional
capabilities include GPIB or
RS232C interface to handle data
output and panel setting data, a
memory card with a capacity of
256 K, mathematical functions,
remote controls, alarms, outputs
up to four points and °F range data
display. The RD3721 comes with an
electronic pen lift and printer. The
RD3722 comes with a manual pen
lift. Both units provide high speed
recording (1600 m/sec max), an
auto span shift mode and partially
expanded-scale recording, whereby
any portion within full scale can be
expanded or reduced for each pen.

Specifications

Measurements

Drive System: Automatic null-balancing

digital servo mechanism with brushless
DC servomotor

Type of Input: dc V, 1 mV to 200V FS;
T/C Types J, K, E, T, N, C, J DIN, T
DIN, R, S, B, Kp vs Au7Fe; RTD Pt100,
Pt50, Ni100

Reference Junction Compensating
Accuracy (T/C): ±0.5°C (10.9°F) for K,

E, J, T, N, C, J DIN, T DIN (and KP vs
Au7Fe); 1°C for R, S and B

Filter: 0.1, 1 Hz or OFF (selectable)
Zero Set: Adjustable
Measuring Cycle: 135 Hz
Standard Pen Offset Compensation:

Average, max/min recording selectable,
resolution on time axis: 0.05 mm,
automatic sweep function for pen offset,
data selectable pen offset compensation
reference pen

Input Impedance: Approx 1Ω
(Vdc and thermocouple)

Allowable Source Resistance:

<1 KΩ (Vdc and thermocouple)

Temperature Coefficient:

Zero Drift: 0.05 µV/°C +0.01%

of range/°C

Full Scale: 0.01% of range/°C

Maximum Allowable Input Voltage:

250 Vdc

Maximum Common Mode Voltage:

250 Vrms AC

Common Mode Rejection:

More than 150 dB at AC

Normal Mode Rejection:

More than 50 dB at 50 or 60 Hz

Recording And Printing

Pens: Disposable felt-tip pen cartridges

(analog data)

Remember

to Order

Extra Pens

and Paper!

Printing System: Wire-dot printer using
ribbon cassette (digital data)

Effective Recording Span:

250 mm (analog data)

Pen Offset Between Channels:

Approx 4 mm on the time axis

Number of Channels: 1, 2, 3, or 4
Recording Colors: First pen is red,

second pen is green, third pen is blue,
fourth pen is brown

Recording Accuracy: Measurement
accuracy plus ±0.2% of effective
recording span (including non-linearity,
deadband and error between ranges)

Maximum Pen Speed:

Approx 1600 mm/s (63 in/s)

Maximum Pen Acceleration:

Approx 8G
Printing Rate: Approx 1.5 sec/line

(for RD3721 only)
Chart: Z-fold chart, 270 mm x 20 m

(10.6" x 65'); optional roll chart,
270 mm x 20 m (10.6" x 65')

Chart Speeds: 10 to 1200 mm/min
and mm/h (1 mm steps), and 0.5 to

45.0 in/min and in/hr (0.1" steps)

Change of Chart Speed (Optional):

Changes chart speed with remote
control signals

Record ON/OFF Selectors:

Independently provided for each channel
on front panel (ON: measurement/
recording, OFF: measurement)

Pen Lift: All pens are lifted and lowered
simultaneously (for RD3721 only)

Chart Drive: Pulse motor drive
Chart Speed Accuracy:

±0.1% (at recording of longer than 1 m)
Digital Data Printout: Time, chart

speed, channel number (tag number),
measured data and engineering unit
are printed out at the following intervals:

Chart Speed (1 mm = 0.03937)

Printing

mm/min mm/h Intervals

1200 to 300 – 1 min

299 to 30 – 10 min

29 to 10 1200 to 120 1 h

– 199 to 60 2 h
– 59 to 40 3 h
– 39 to 20 4 h
– 19 to 10 12 h

S-46

RD3722-42, $4704,
shown smaller than
actual size.

Tag Number Printout: Tag number can

be printed out in place of channel number,
up to 7 alphanumerics (for RD3721 only)

Alarm Printout: Channel number, alarm
type and the time of alarm ON/ OFF are
printed (for RD3721 only)

Scale Markings Printout: 0% and 100%
scale values can be printed out at the
same interval as digital printout (for
RD3721 only)

Program List Printout: Contents of
entire setting memory can be listed
on the chart (for RD3721 only)

Manual Printout: Time and measured
data for all channels can be printed out in
a single line by depressing the MANUAL
PRINT key (for RD3721 only)

Message Printout: Message of up to
70 characters can be printed by
depressing the MANUAL MESSAGE key
(message 0), or by external contact signal
(message 1 to 4; optional, up to 4
channels), for RD3721 only

Change of Chart Speed Printout: Chart
speed and time can be printed out at the
change of chart speed (for RD3721 only)

Pen Offset Compensation: ON/OFF
Printout: ON/OFF mark and time can be
printed out (for RD3721 only)

Change of Range Printout: Changed
contents and time can be printed at the
change of range, on auto span shift mode
(for RD3721 only)

Partially Expanded-Scale Recording:

Any portion within full scale can be
expanded or reduced for each channel

Auto Span Shift Mode: Automatically
shifts to ±50% of span, and recording
continues when the input exceeds the
measuring span

External Input Span: Small error of
external converter can be corrected by
setting the span with actual input voltage
(zero is span left, full is span right)

Display

Type of Display: Vacuum fluorescent

display (5 x 7" dot matrix, blue),
20 characters for each channel

S