STH Pump Controller

Overview:

The ML175 STH Pump Controller is used to control the flow of biological liquids in Langendorff or other isolated perfused organ experiments, by controlling the speed of the peristaltic pump. It can be used to provide average constant perfusion flow or pressure. The STH Pump is included as part of the ADInstruments Langendorff System.

The STH Pump Controller connects to a Bridge Amp and Pressure Transducer and uses a negative feed-back control circuit to alter a flow rate signal sent to a Peristaltic Pump.Therefore a constant perfusion pressure can be maintained in the perfusate line, typically within ±1 mmHg. It can also be set to a fixed flow signal manually, when working under constant perfusion flow conditions. The flow rate and pressure signals are monitored, displayed and recorded with a PowerLab system and LabChart software.

Hardware:
The STH pump will only function with PowerLab data acquisition units and therefore is not suitable for use with other data acquisition systems.

Features:

• Electronic feedback control by applying a pressure signal to the pressure input, the controller can constantly adjust the flow rate of the system to maintain constant pressure perfusion.
• Integration with PowerLab and the Gilson Minipuls 3 peristaltic pump for online measurement of vascular or coronary flow, eliminating the need for cumbersome hydrostatic columns to deliver constant pressure perfusion.
• Adaptable to a range of pumps
• A control voltage delivered to the pump in constant flow mode. Increasing the voltage increases the speed of the pump and hence the flow rate.
  

Applications:

The STH Pump Controller is a constant flow or constant pressure controller for a peristaltic pump and is used to control the flow of biological liquids in Langendorff or other isolated perfused organ experiments.

For more information see the Langendorff Heart application page.

Specifications:

Controller Operation

• Modes: Constant Flow or Constant Pressure
• Flow Rate Error: ± 3% (~3 s to stabilize after change)
• Constant Pressure Error: ± 1 mmHg
• Drift in Constant Pressure: < 1% over 30 min

Pump Control Signals

• Run/Stop Control: Contact closure (Run : contact closure)
• Forward/Reverse Control: Contact closure (Reverse : contact closure)
• Pump Control Voltage: 0 to +5 V (+5 V : max pump speed)

Flow Rate Output

• Flow Rate Signal Range: 0 to +5 Volts (+5 V : max flow rate)
• Output Filtering: 0.5 Hz or 1 Hz, 2nd order, low-pass, switch-selectable

Pressure Input

• Max Input Voltage: ± 15 V
• Input Impedance: 100 kΩ
• Input Gain range: x1 to x100, adjustable from rear panel (to suit a wide variety of external signal conditioners)

Operating Requirements

• Power Requirements: +9 V @ 100 mA, ±18 V @ 50 mA
• Operating Conditions: 5–35 °C, 0–90% humidity (non-condensing)

Physical Configuration

• Dimensions (w × h × d): 20 x 6.5 x 27.5 cm
• Weight: 1.3 kg

ADInstruments reserves the right to alter these specifications at any time.