KD Scientific Gemini 88 - Manual (Page 7)

5
KDS Gemini 88
Features
Pressure and Speed
Pump 33 can deliver up to 106.60 ml/min with a 140 ml syringe, and is capable of pres-
sures of up to 99.5 PSI with a 20 ml syringe.
Independent Syringe Diameters and Rates
In the Proportional Mode, separate syringe types and rates may be set.
Variable Syringes
Enter the inside diameter of the syringes being used.
Modes of Operation
Auto Stop
Both syringes will operate at same rate and stop when either syringe reaches a
limit stop.
Continuous Run
With both syringes operating at same rate, when end of travel is reached, the pump
automatically reverses the direction of travel for both syringes. The external valves,
optionally attached to the syringes, will be automatically activated or deactivated.
Proportional
Pump operates as in Auto Stop, but independent rates and diameters are set for
each syringe.
Parallel/Reciprocal Operation
Syringes may pump in the same direction (parallel) or opposite directions (reciprocal).
External Connections
TTL
Allows pump operations to be synchronized with external devices or by a person at a
distance from the pump. Direction of pump travel can be set via a TTL pin. Also, TTL
pins are used to control an external valve for refilling and provide an output to indicate
whether or not the pump is running. Additional TTL pins are available for general use.
RS-232
Multiple pumps can be chained together and remotely controlled from a computer or
any device communicating via RS-232.
Non-Volatile Memory
All operational data entered into the pump from the keypad or requested to be saved via RS-
232, will be stored. On power up, all settings from when it was powered down will be
recalled and the display will blink until the pump receives its first command.
Stall Detection
An optical detector on each motor is used to verify expected movement of the motors. If
motor is prevented from turning due to jamming or kinking of the tubing, the pump stops and
the display indicates a stall condition by blinking the run light and the syringe direction light
of the stalled syringe. Pump 33 employs a microcontroller which controls a small step angle
stepping motor that drives a lead screw and half nut. Microstepping techniques are used to
further reduce the step angle making flow pulsation negligible. A keypad is used for entry of
operating data to the pump or data can be entered via RS-232. The microcontroller calcu-
lates the cross-sectional area of the syringe selected and calibrates the flow rate.