PUMP SPECIFICATION-DMS
To define the metering pump to use, please add these
sections to the basic dosing and/or metering pump specifications
- Dosing
pumps shall be motor driven with positive movement during both suction and
discharge strokes. Neither Solenoid driven type pumps nor motor driven
pumps that use a spring to complete the pumping cycle is acceptable.
- The
pump’s stroke length will always be 100%. No adjustment to the stroke
length, to regulate flow or, for other reasons, is acceptable.
- A
digital keypad will be used to set the required flow rate.
- Only
pump speed will be changed to regulate flow.
- The
pump shall maintain a repeatable accuracy throughout a full range of the
pump’s performance capability. A true 100:1 turndown ratio shall be
maintained (i.e. a pump rated at 2 gph shall be equally accurate at .02
gph as at 2gph).
- Accuracy
shall be repeatable when the flow rate is changed. If the flow is changed, and then reset
to the original flow,
the original flow shall be achieved without recalibration.
- The
pump shall be driven by an internal synchronous drive type electric motor.
- The
pump enclosure shall be rated to IP65 standards.
- The
pump shall be listed by UL as a chemical process pump (category RBOG).
- The
pump shall include an electronic lock to prevent tampering.
- The
pump shall include manual, analog and pulse control settings. If the
analog mode (4-20 mA) is used, the pump shall
have onboard ability to extend or invert the input signal (20-4mA, 0-20 mA or 20-0 mA)
- The
pump shall display the actual flow in US
standard (GPH) or Metric standard (l/hr or ml.). Changing from one unit of
measure to the other shall be an easily accomplished, field settable,
function.
- The
pump shall include a 100% button to aid in priming. When priming is
complete, the pump will automatically return to preset conditions.
- Pump
check valves shall be of a cartridge design for ease of maintenance. The
discharge and, at least, one of the suction valves shall be
interchangeable. Direction of flow shall be clearly marked on each check
valve to insure correct installation.
- When either the Polypropylene or PVDF
pump is used, the tubing type end connections shall be designed to seal to
a maximum pressure of 260 PSI.
Stainless steel wetted pumps, only, shall use NPT connections.
- The
pump shall be a Grundfos model DMS, Digital Dosing™ pump.