FAQs
How can I drive Disc Pump™?
Disc Pump™ should be driven at its resonant frequency by a frequency-tracking circuit. The drive PCB provided with our Evaluation Kits uses a simple microprocessor to achieve this; other approaches are also possible. Note that PWM drives of the type commonly used to drive DC motors are not suitable for driving Disc Pump™.
Can I integrate Disc Pump™ drive circuit into my own PCB?
Yes. The recommended drive circuit will occupy a small area of your product PCB. Our Disc Pump™ Drive Guide (see Downloads section above) provides you with a reference circuit and guidance notes, and we are also able to provide reference firmware. Given the need to produce a custom board, this step typically follows a successful feasibility demonstration using our Evaluation Kit PCB.
How should I mount Disc Pump™?
Disc Pump™ can be mounted in any orientation. We recommend a ‘soft’ mounting for Disc Pump™. One way to achieve this is to plug the pump’s inlet and outlet ports into a compliant manifold block, providing both pneumatic connection and mechanical mounting. The pump can also be mounted using features provided on the pump body; in this case we recommend using a compliant o-ring (e.g. 1.42 ID X 1.78 CS mm) and nylon M2 bolt. Our Evaluation Kit circuit board has two surface-mount, threaded steel studs that the pump can be mounted on. Should you wish to use the same part, it is Wurth Elektronik 9774050243R.
Should I use a filter with Disc Pump™?
We recommend the use of a filter with a pore size of 1.2μm or less in order to prevent the ingress of particulates that might otherwise limit the lifetime of the pump.
What do you mean by "SDC" and "PDC" Disc Pumps?
Disc Pump™ has two pumping chambers or cavities. An SDC ("Series Double Cavity") Disc Pump™ has these chambers arranged in series, so that the outlet from the first cavity feeds into the inlet to the second, allowing higher pressures to be generated. A PDC ("Parallel Double Cavity") has the inlets in common, and the outlets in common, allowing higher flows to be generated.
Can I convert an SDC Disc Pump™ to a PDC Disc Pump™?
The valves in SDC and PDC Disc Pumps are assembled differently to ensure that there is no net pressure difference between the two cavities in operation. We therefore recommend that you run them only in their intended configuration.
What is the working temperature range of Disc Pump™?
Our BL Series pumps are specified for a range of 5 - 40ºC. Our upcoming XP Series offers a wider termpature range of -25 to +55ºC. Disc Pump can be run outside this range (helped by its lack of sliding / rotating parts); please contact us if you would like to discuss further.
What is the working humidity range of Disc Pump™?
Disc Pumps have been tested from 5 – 95% humidity (non-condensing).
Can I drive a Disc Pump™ to its stall pressure?
Yes, the pump can be driven to its stall pressure ( i.e. maximum pressure or vacuum at zero flow) without damage. This is also known as "dead heading".
Will the pump restart against any pressure head?
Yes, the pump can be restarted normally against any pressure head.
Can I connect multiple Disc Pumps in series or parallel?
Yes, pumps can be connected in series (to generate more pressure) or parallel (to generate more flow) in the normal way.
Can Disc Pump™ be used to pump gasses other than air?
Yes, so long as the speed of sound in the gas (or gas mixture) is similar to that in air. Disc Pump’s performance depends on the speed of sound in the gas mixture being pumped and it has been designed to work optimally with air. Mixtures of gasses with a similar speed of sound can also be pumped, however the pump will not work well with e.g. pure helium.
