High Pressure Proportional Control Dosing Pump

The AT1-AM is a high pressure dosing pump which offers proportional control to an external signal, either an industry standard 4-20mA or a pulsed input from a compatible controller.

AT1-AM High Pressure Proportional Control Dosing Pump Introduction

The AT1-AM is a high pressure proportional control solenoid dosing pump which is designed to precisely meter a small amount of chemical into a process.  The AT1-AM has a number of operating modes:-

• Constant flow rate - where the chemical delivery is set manually using the front mounted dial.
• Proportional to a pulsed input signal - this can come from a water meter or compatible instrument, such as our P7685, P7687 or P6587.
• Proportional to a 4-20mA output - supplied from a compatible instrument or process controller.

When operating in proportional mode the external control signal automatically varies the frequency or number of strokes the dosing pump makes per minute.  This allows the pump to increase or decrease the flow rate depending upon the instruction from the instrument making it ideal for flow proportional dosing or pH correction applications.

The AT1-AM can be started / stopped from a volt free input, which is designed to operate as a low level cut-off.  The volt free input can be connected to an optional Low Level Float Switch or Suction Lance Assembly to prevent the pump from running when a low chemical level is present.  The low level cut-off can be used in all operation modes.

In addition to the low level cut-off, the AT1-AM includes a flow verification input from an optional flow sensor and a volt free alarm output.  This can be used to output to a piece of control equipment or an indicator, if the dosing pump enters an alarm condition.

The AT1-AM can be attached to a flat vertical surface, for surface mounting installatio, or used with the optional foot-mounting bracket for foot mounting applications. Designed primarily for water treatment, waste-water treatment, effluent treatment and process control, the AT1-AM is a simple and reliable dosing pump for high pressure dosing applications.

The AT1-AM is powered from a switch mode power supply which is suitable for a mains supply of 100 - 240 V AC 50hz or 60Hz and is designed to IP65 specification.

AT1-AM Dosing Pump Outputs

The AT1-AM dosing pump series are available with the following outputs:-

AT1-AM - Manual Control

The AT1-AM has a number of operating modes, each of which is simple to setup and integrate into a process.  The AT1-AM can be used in a manual operation mode (although our AT1-BX or AT1-BL models may be more appropriate) by switching the selector switch.  The output of the pump can then be controlled using the front mounted potentiometer, across 0 - 100% of the rated output.

AT1-AM Proportional to Pulsed Input / Flow Proportional Dosing

The AT1-AM is designed as a high pressure low flow rate dosing pump to dose proportional to a pulsed input signal.  This volt free input signal can be supplied from a Water Meter or a process controller, which provides a pulsed output.

When dosing proportional to the flow from a water meter, the water meter provides pulses based on the measured flow rate, eg. 1 pulse per litre.  As the flow rate increases or decreases the number of pulses which are transmitted to the dosing pump increase or decrease, causing the dosing rate to increase or decrease allowing the dosing pump to maintain an even delivery of chemical into the flow.  This makes the model series ideal for water treatment and boiler dosing applications.

When dosing proportional to a process controller, the instrument will supply a pulsed output to the dosing pump.  This causes the pump speed or number of strokes per minute to increase or decrease proportionally.  The benefit of this is that the chemical reagent is delivered more quickly the further away from the setpoint and a smaller amount as it approaches the setpoint, reducing chemical usage and minimising the risk of over-dosing.

To ensure compatibility with a wide range of external equipment, the AT1-AM can multiply or divide the incoming pulses. The following multiplication and division modes are available:-

• 1:1 mode - where 1 pulse from the control equipment results in 1 stroke of the pump
• 4:1 mode - where 4 pulses from the control equipment results in 1 stroke of the pump
• 10:1 mode - where 10 pulses from the control equipment results in 1 stroke of the pump
• 1:n mode - where 1 pulse from the control equipment results in n strokes of the pump. N can be any number from 1 - 10 and is set using the front dial.

In 1:n dosing mode, at the first signal received, the AT1-AM will make n strokes at the maximum speed.  The AT1-AM will then measure the time between the successive pulses (maximum period of 60 seconds) and distribute the strokes evenly across the time period to ensure consistent dosing.

AT1-AM Dosing Pump Proportional to a 4-20mA signal

In addition to dosing proportional to a pulsed input signal, the AT1-AM is also a 4-20mA proportional dosing pump, allowing the pump speed to be automatically regulated.

With a 4-20mA input the AT1-AM will automatically stop when the signal is 4mA.  When the signal is 20mA the pump will dose at the percentage of the output selected by the top mounting dial.  The 20mA value or maximum value can be selected across a range of 10 - 100% of the pumps rated output.

AT1-AM Flow Verification, Level Input and Alarm Output

The AT1-AM includes a number of inputs which can be incorporated into normal pump duty, if required, each of the inputs enter the pump into an alarm condition which stops the pump from operating and these can be set to trigger an alarm output.

The alarm output is a volt free contact which can be used to trigger audible alarms, beacons, or feedback into an instrument, BMS system or PLC as required.

The low level input is designed to be triggered from an optional suction lance assembly or a Low Level Float Switch preventing the pump from operating when a low chemical level is present.  The low level input is a volt free input.  It can trigger the alarm relay which can be wired to external equipment.

The flow verification input is designed to work with an optional flow sensor.  The flow sensor compares the output from the pump with the number of strokes that the pump makes.  If the flow sensor fails to measure a chemical reagent triggering the flow sensor after 6 strokes, then it will trigger the alarm relay output.

The AT1-AM is designed to IP65 specification, making it suitable for indoor or outdoor operation and can be foot mounted or surface mounted to a flat vertical surface.  Power is via a switch mode power supply, meaning that an AC supply voltage of 100 - 240 Volts at 50Hz / 60Hz can be used to power the pump.

AT1-AM Wetted Parts / Liquid End

The AT1-AM is designed as a chemical metering pump for industrial usage and as such has wetted parts developed specifically for chemical handling.

As standard the AT1-AM is available with a liquid end manufactured in either PVC or PVDF, with Ceramic or PTFE balls and a PTFE diaphragm.  The seals and O-rings are available in either Viton (© DuPont / Chemours) or EPDM with PTFE O-rings available as an option.

Our chemical compatibility database can be used to check the wetted parts.  Please don't hesitate to get in touch if you are unsure.

Priming the liquid end for dosing couldn't be simpler.  The AT1-AM is supplied with tubing and has an adjustable bleed valve located on the pump head.  Loosening the bleed valve allows the chemical reagent to be circulated through the pump to quickly and easily to ensure accurate dosing.

What's in the box with the AT1-AM?

The AT1-AM is supplied complete with everything required to begin metering chemical reagents into a process.

Supplied with the dosing pump itself are:-

• Injection Valve with 3/8" and 1/2" BSP male threaded connections
• Foot-valve & Strainer assembly
• 1 metre of discharge tubing
• 2 metres of suction / bleed tubing
• Surface mounting kit

An optional foot mounting bracket can be included for no additional charge if requested.

AT1-AM Features & Benefits

The AT1-AM is a robust, reliable and accurate chemical dosing pump, designed for high pressure operation or where a small amount of chemical reagent is required to be accurately metered into a process from an external signal.  Ideal for either stand alone operation or integration with process control equipment which offer a pulsed output (PFM signal) or an industry standard 4-20mA output signal.

Designed to IP65 specification, the AT1-AM is ideal for locating either internally or externally.

As a proportional control dosing pump, the AT1-AM is able to work with an industry standard 4-20mA input signal or from a pulsed input signal commonly provided from a Water Meter or control device.

The AT1-AM makes commissioning the metering pump as simple as possible.  The 4-20mA output can be regulated using the front mounted dial and the pulsed input signal can be either multiplied or divided as required.  This ensures full compatibility with most processes.  The AT1-AM is self priming and using the adjustable bleed valve ensures that this is accomplished swiftly and cleanly.

There are a number of additional safety measures on the AT1-AM.  These include the volt free input which can be used with an optional Low Level Float Switch or Suction Lance Assembly and the flow verification input (for use with an optional flow sensor), which will automatically stop the dosing pump from operating in the event of a low chemical level or if the output flow is not being measured.  Both of these options can be set to trigger the alarm relay output which can be directly connected to an indicator such as an audible alarm, a BMS or PLC or directly into another of our proportional control Dosing Pumps if two or more pumps are being used in tandem.  The alarm functionality can also be disabled completely if required.

The AT1-AM is designed specifically for chemical dosing with the wetted parts suitable for many chemical reagents, with a liquid end manufactured in PVC or PVDF, a PTFE diaphragm, Ceramic or PTFE balls and either Viton, EPDM or PTFE seals and O-rings. Designed to IP65 specifications, the AT1-AM is suitable for mounting outside.

The AT1-AM is available as the following model types:-

• AT1-AM-20-015 for an output flow rate of 1.5 Litres / Hour at 20 Bar pressure
• AT1-AM-18-02 for an output flow rate of 2.0 Litres / Hour at 18 Bar pressure

As the AT1-AM series are powered from a switch mode power supply which is able to accept a mains supply of 100 - 240 VAC at 50Hz / 60Hz, the AT1-AM is also suitable for export markets.

As part of our Red Dosing Pump range, the AT1-AM is rated hot for continuous dosing duty, and the pump is designed to provide for a long trouble free life of accurate chemical dosing.