Myron L 762 User Manual
Page 3
Introduction
SECTION 1
Introduction
1.1 SCOPE
This manual provides the necessary information to install,
operate and maintain the Myron L Company’s 750/760 Series
Resistivity Monitors. Sections 1 thru 3 provide the user with a
Monitor’s applicational description, mounting, wiring and
operational procedures. Section 4 identifies their primary
components and provides the user with easy-to-use calibration,
and preventive maintenance procedures.
Section 5 (Appendix) provides Replaceable Components
Charts.
1.1.1 FUNCTIONAL DESCRIPTIONS
All models have drip/weather-proof housing which can be panel
or surface mounted. The 750 models are a compact 6.0" x 5.0"
(152mm x 122mm). The 762 is 6.0" x 10.8" (1 52mm x 275mm).
All model front panels are equipped with bright green and red
LEDs that indicate “Above” or “Below” set point readings. Also
standard on all models is a heavy-duty 10 amp Alarm relay,
activating on decreasing readings.
For specific Monitor configurations, reference the following
individual model descriptions:
Model 750
Provides a front panel accessible set point adjustment knob in
place of an analog or digital meter readout display.
Model 752
Set point is internal to discourage unauthorized adjustments.
Standard front panel is equipped with a linear analog meter
display and a “SET POINT CHECK” switch.
Model 753
Set point is internal to discourage unauthorized adjustments.
Standard front panel is equipped with a digital LCD meter
display and a “SET POINT CHECK” switch.
Model 762
Set point is internal to discourage unauthorized adjustments.
Standard front panel is equipped with a three (3) Range select
switch (0-20, 0-2, 0-0.2 megohm), a linear analog meter display
and a “SET POINT CHECK” switch.
1.1.2 MONITOR APPLICATIONS
1
Deionized (Dl) and distillation ultra-pure treatment
systems
2
Electronics
3
Food Processing
4
Plating
5
Power Plants
6Laboratories
1.2 MONITOR SPECIFICATIONS
RANGES:
0-20 megohm-cm
0-2 megohm-cm
0-200 kilohm-cm
0-500 kilohm-cm (Model 750 only)
0-20, 0-2, 0-0.20 megohm-cm, (Model 762 only)
READOUT:
Model 752: 2
1
/
2
" (63mm) Analog
Model 753:
1
/
2
" x 3
1
/
2
Digit (13mm) Digital
Model 762: 4
1
/
2
" (114mm) Analog
ACCURACY:
Model 753:
±
1 % of span
Other Models:
±
2% of span
SENSITIVITY:
0.5% of span
STABILITY:
0.05% of span
REPEATABILITY:
0.1% of span
CELL INPUTS:
1 Input (standard)
3 Cell input (optional 762 only)
RELAY FUNCTION:
Single set point control:
Continuously adjustable 0-100% of span
Indicators:
“ABOVE” (green) and “BELOW” (red) set point LEDs
Contact Rating:
SPDT 10 amp @ 250 VAC, 30 VDC. Relay activates on
decreasing readings
POWER SPECIFICATIONS:
115 VAC, 50/60 Hz
±
15%, 25mA
220 VAC, 50/60 Hz
±
15% (Optional)
AMBIENT TEMPERATURE RANGE:
-22
°
F ( -30
°
C) to 140
°
F (60
°
C)
CONSTRUCTION:
Fully gasketed heavy-duty ABS for corrosion resistance,
NEMA type 3 rated
WEIGHT:
(750 Series) 2 Ibs (0.9 kg)
(762) 3 Ibs (1.4 kg)
1