Myron L 729II - Manual (Page 9)

I. INTRODUCTION
Thank you for selecting one of the Myron L Company’s new 720
Series II Monitor/controllers. The 720 Series II is based on input
from ‘you’ - our customers, time proven designs, and many years
of instrumentation experience.
Since 1957, the Myron L Company has been providing customers
with quality products at an affordable price by designing and
producing products that are Accurate, Reliable, Simple to use.
Quality you have come to rely and depend on.
As you read through this operation manual you will see the 720
Series II is truly designed to be user friendly with simple to install
options and accessories as conditions or applications change.
This manual is actually more complex than the 720 Series II
Monitor/controller, but must be to address all the variables.
Where applicable the Original Equipment Manufacture (OEM)
models are separated as necessary to clarify and define their
differences. As defined by the Myron L Company, an OEM model
does not have an enclosure. However, many OEMs use our
enclosure just as if it were a standard model, therefore, as an end
user you must decide whether to follow the OEM instructions or
the “standard” models with enclosure.
All OEMs mount the circuit board assemblies in differing locations
making it impossible for us to describe exactly where to find them.
By looking in section V. for the Main circuit board (CB) assembly,
you will have a picture of what it looks like. If your OEM has a
display, follow the display harness back to the Main CB. Once
located you will be able to locate any installed options by following
the harnesses, i.e. 4A (4-20mA output).
All Myron L Monitor/controllers are CE approved for safety and
EMF requirements.
A. SCOPE
This operation manual provides the user with the necessary
information to install, operate and maintain the
Myron L Company’s 720 Series II pH & ORP Monitors/controllers.
Section I. Descriptions, Applications, Specifications.
Section II. Installation; mounting, wiring and set up.
Section III. Options and Accessory installation procedures.
Section IV. Operating Procedures.
Section V. Component Identification; Identifies their primary
components and provides the user with easy-to-use
calibration and preventive care procedures.
Section VI. Options & Accessories List.
Section VII. Replacement Components.
Section VIII. Warranty information.
Section IX. Glossary, definitions.
Section X. Notes.
Section XI. Addendum.
1. FUNCTIONAL DESCRIPTIONS
All models except OEMs have water & corrosion resistant
IP65/NEMA 4X enclosures suitable for panel, bench or surface
mounting. The 720 Series II are a compact 6.0” (152mm) x 4.8”
(122mm).
Bright green/red LEDs indicate HIGH/LOW set point readings. All
models except 721II, 724II, 726II, & 729II, (see below) feature a
heavy-duty 10 amp output relay, operating on either increasing or
decreasing readings.
For specific Monitor/controller configurations, reference the
following individual model descriptions.
Models 723II pH & 728II ORP
Digital Monitor/controller. Standard front panel is equipped with a
3 1/2 digit liquid crystal display (LCD), and a “SET POINT” switch
with High/Low LED indicator lights. Single set point is internal to
discourage unauthorized adjustments. A second set point
alarm/control is available as an option. May use an optional 4-
20mA output for PLC or SCADA operations.
Models 724II pH & 729II ORP
Digital monitor ONLY. Standard front panel is equipped with a
3 1/2 digit liquid crystal display (LCD) only, no relay, LED
indicators or set point switch. May use an optional 4-20mA output
for PLC or SCADA operations.
Models 722II pH & 727II ORP
Analog Monitor/controller. Standard front panel is equipped with a
linear analog meter display and a “SET POINT” switch with
High/Low indicator lights. Single set point is internal to discourage
unauthorized adjustments. A second set point alarm/control is
available as an option. 4-20mA output option is available on OEM
models only.
Models 721II pH & 726II ORP
Analog monitor ONLY. Standard front panel is equipped with a
linear analog meter only, no relay, LED indicators or set point
switch. 4-20mA output option is available on OEM models only.
2. APPLICATIONS
pH & ORP
Reverse Osmosis
Process Control
Seawater Desalinization
Wastewater Treatment
Food Processing
Plating
Power Plants
Laboratories
Printing
Boiler
Cooling Tower
Deionization (DI) and Distillation Ultrapure Water
Treatment Systems
Electronics
Pharmaceutical
Are just a few of the many applications
B. SPECIFICATIONS
RANGES:
pH 0-14
ORP ±2000 mV
DISPLAY:
Models 721II, 722II & 726II, 727II:
2 1/2” (63mm) analog meter
Models 723II, 724II & 728II, 729II:
1/2” (13mm) 3 1/2 digit LCD
NOTE: 3 1/2 digit LCD may be replaced with a 3 1/2 digit Back lit
LCD - available as an option.
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