malema.com
Introduction
The M-200X Series flow switches are engineered and field tested for sensing increasing and decreasing flow rates of gases or
liquids. Pressure variation effects are minimal. This series features such versatility, economy, and accuracy that they can be used
in virtually any application requiring fool-proof inexpensive flow detection.
Operation
The operating principle is based on a free floating magnetic piston which responds only to the motion of fluids within the line,
not to static or system pressures. In the presence of fluid flow, controlled movement of the piston actuates an external hermeti
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cally sealed reed switch thus producing the required signal. This signal can be used to actuate audible or visual alarms as well
as relays, or other control. Piston travel is short which insures low hysteresis. Pressure drop across flow switch varies from 0.035
to 2 psi (at maximum flow rates for air and liquid). Universal mounted units are outfitted with a spring which resets the piston.
The spring is held in place using a perforated disc.
llustrated is the M-200 Model with 1/2” ports.
Storage and Handling
Storage conditions
Store the product under packed condition in an anti-static bag. The storage place shall be free from moisture, mechanical shock
and vibration. The ambient temperature shall be between 0°C and 60°C and the humidity between 5% and 80% R.H. without
condensation.
Unpacking and Product Inspection
On delivery, check the product for damage. Confirm that the model code on the label matches the specification in the purchase
order.
Installation Instructions
This product can be mounted in any orientation. Adequate filtration and sealing procedures should be used when mounting in
flow lines.
Operating Environment
Choose a location with an ambient temperature of 10-35
°
C and relative humidity value <80% RH without exposure to direct
sunlight. Avoid environments with high electromagnetic noise or vibration. Make sure that the module is protected from corrosive
liquid or water splashes. For best performance avoid corrosive environments since they may degrade the performance of
the electronics after a period of time. Easy access for maintenance and inspection is always recommended.
Construction
The M-200 Series comprises a Body, piston, and Retaining rings. Selecting a flow switch begins with selecting the body; this
series is available in 316 Stainless Steel. The M-200 series contains one moving part (i.e. the piston) and two retaining rings that
are in the fluid path. Construction of the piston is important from a design perspective. We manufacture three types of pistons
(It is critical to select the correct piston for your application): 316 Stainless Steel, PTFE encapsulated, and Special All-Metal Piston.
1. The standard piston is a 316 Stainless Steel piston with epoxy to hold the magnet in place. This piston is recommended for
non-aggressive fluids and inert gases. Stainless Steel retaining rings are typically used with this piston type.
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