Myron L 767 - Manual (Page 3)

SECTION 1
Introduction
1.1 SCOPE
This manual provides the user with the necessary information to
install, operate and maintain the Myron L Company’s 750/760
Series Conductivity Monitors. Sections 1 through 3 provide Monitor
applicational descriptions, mounting, wiring and operational
procedures. Section 4 identifies their primary components and
provides the user with easy-to-use calibration and preventive care
procedures.
Section 5 (Appendix A) provides the 750/760 Series Monitor’s
Replaceable Components Chart.
1.1.1 FUNCTIONAL DESCRIPTIONS
All models have drip/weather-proof housings suitable for panel,
bench or surface mounting. The 750 models are a compact 6.0"
(152mm) x 4.8" (122mm). The 767 model is 6.0" (152mm) x 10.8"
(275mm).
Bright green/red LEDs indicate below/above set point readings.
All models except 756 feature a heavy-duty 10 amp output relay,
operating on either increasing or decreasing readings.
For specific Monitor configurations, reference the following
individual model descriptions.
Model 755
Small controller only. Provides a front panel accessible set point
adjustment knob in place of an analog or digital meter readout
display.
Model 756
Small monitor only. Standard front panel is equipped with a linear
analog meter display only (no relay, LED indicators or set point
check switch).
Model 757
Small analog monitor/controller. Single 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 758
Small digital monitor/controller. Single 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 767
Large analog monitor/controller. Single set point is internal to
discourage unauthorized adjustments. Standard front panel is
equipped with a three (3) range select switch, analog meter display
and a “SET POINT CHECK” switch. Options include three (3) cell
input capability and dual set point control.
1.1.2 APPLICATIONS
1 Reverse Osmosis
2 Process Control
3 Seawater Desalinization
4 Waste Treatment
5 Food Processing
6 Power Plants
7 Laboratories
1.2 SPECIFICATIONS
RANGES:
Refer to Conductivity/ppm Ranges sheet on Page 3 for
Conductivity Ranges.
READOUT:
Model 756: 2 1 / 2 " (63 mm) analog meter
Model 757: 2 1 / 2 " (63 mm) analog meter
Model 758: 1 / 2 " (13 mm) 3 1 / 2 digit LCD
Model 767: 4 1 / 2 " (114 mm) analog meter
ACCURACY:
Model 758: ± 1 % of span
Other Models:
±
2% of span
SENSITIVITY:
0.05% of span
STABILITY:
0.05% of span
REPEATABILITY:
0.1% of span
CALIBRATION CHECK:
Built in
RECORDER OUTPUT:
0-10 VDC @ 5 mA max. (linear); standard on all models
CELL INPUT:
1 (optional 3 Cell Input available on Model 767)
RELAY FUNCTION:
Models 755, 757, 758 and 767:
Single set point control continuously adjustable 0-100% of
span
Indicators:
“ABOVE” (red) and “BELOW” (green) set point LEDs
Contact Rating:
SPDT 10 amp @ 250 VAC, 30 VDC. Relay operates
increasing or decreasing reading (selectable).
Optional on Model 767 only:
Dual set point control, with above specifications
POWER SPECIFICATIONS:
115 VAC
±
15%, 50/60 Hz, 25 mA
220 VAC (User changeable)
DIMENSIONS 750 SERIES:
6.0" (152 mm) H x 4.8" (122 mm) W x 3.8" (96 mm) D
DIMENSIONS 760 SERIES:
6.0" (152 mm) H x 10.8" (275 mm) W x 3.9" (99 mm) D
AMBIENT TEMPERATURE RANGE:
-22
°
F (- 30
°
C) to 140
°
F (60
°
C)
HOUSING CONSTRUCTION:
Fully gasketed heavy-duty ABS for corrosion resistance. Rated
NEMA type 3.
WEIGHT:
750 Series: 2 Ibs. (0.9 kg)
760 Series: 3 Ibs. (1.4 kg)
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