BUBBLE CLEAR - Automatic cycle in a linear system providing a means
of removing small bubbles of air or gas from the pump chamber.
Selected from the control panel.
CALIBRATED - Any gauge, meter, pump, etc. that has been
systematically checked / adjusted to a known, certified standard.
CAVITATION - The sudden formation and collapse of bubbles in liquids
by means of mechanical forces creating low pressure.
CHANNEL - IVEK offers both single and multiple channel
configurations. A channel refers to a single Motor/Base or Actuator
Module driven by a Controller Module. Single Channel systems are
often bench-top units. Multiple Channel systems are often integrated
into a production application to fill many vessels at once.
CLEAN LIQUIDS - Application liquids or reagents which have been
prepared via a filtration, distillation or other sterilization
process to a controlled level of acceptable molecular and(or)
biological contamination.
CLEAR FAULTS - 1) The 'clear faults' command must be issued prior to
any commands which would cause motion in a Actuator Module or motion
control device in a system which is faulted. This command responds
with the identity of the fault being cleared and additional
information for certain faults. 2) To manually reset the system due
to any fault condition that may occur.
COMMAND STRING - A series of characters sent to a controller
containing a serial interface to control its operation.
COMPATIBLE LIQUIDS - Any liquid that has been evaluated and qualified
as having no negative effect on the liquid management system
components.
CONTINUOUS METER - Operating mode to produce a continuous liquid flow
as long as a control signal (and liquid) is supplied. Note: This mode
only applies to the Digifeeder 2002 system and utilizes two pumps
driven by linear actuators that alternate in operation between intake
and discharge cycles. All other systems use Meter mode.
CONTROLLER MODULE - The module in a system containing the electronics
for controlling and monitoring system operations.
CYLINDER - Pump Module component where the piston is housed.
DEAD VOLUME - Liquid occupying areas within the system which is not
replaced during each cycle or removed during a purge.
DEFLECTION - 1) The deviation from zero or other neutral value by the
indicator of a measurement instrument. 2) The movement of a structure
or structural part as a result of stress.
DEGASSING - Generally, referring to the evacuation of free gasses
from the application liquid.
DIRECTION - 1) Controller mode function used to select forward or
reverse motion of liquid flow through the Pump Module and liquid
circuit. 2) For some rotary systems, flow direction can also
be changed by adjusting the pump displacement angle to the other side
of the "zero" point (zero angle where pump has zero displacement).
DISPENSE MODE - Controller mode function used to deliver a discrete,
specific volume of liquid at a specific flow rate as the result of a
triggering action.
DRAWBACK - Operation which automatically reverses liquid flow at the
end of a dispense to improve repeatability and string breaking. The
drawback volume is generally a fraction of the dispense volume.
DRIVE SYSTEM - 1) The system configuration relative to the controller
and Motor/Base Module including electronics, software, drive motor
and braketry options. 2) Mechanical components that transmit power.
3) Electrical circuitry that controls and powers a motor, solenoid,
or other electrical-to-mechanical converter.
EMPTY MODE - Controller mode function used to return liquid in the
inlet tubing, pump chamber, and outlet tubing to the supply
reservoir, when metering and(or) dispensing operations are completed.
FAULT - A condition where the system controller has detected an
improper condition or state of the equipment. The existence of the
fault will be indicated on the system controller until the fault is
cleared by a specific action.
FAULT DELIMITER - Pertains to a system with a serial interface. A
character, in the response command, which identifies the subsequent
value as a fault identifier and which separates it from preceding
values
FLOW VOLUME - 1) Rotary System: The flow magnitude, (and direction),
relative to the pump size and due to the angular deflection of the
Pump Module cylinder with respect to the "zero" point on the
calibration scale of the specific Pump Module. 2) Linear System: The
flow magnitude, (and direction), relative to the pump size and due to
the selected controller settings.
FLUID SHEAR - The separation of the dispensed liquid from the liquid
remaining in the dispense tip. Optimizing several factors, such as
the dispense tip geometry and dispense rate, improves fluid shear and
the repeatability of the dispense volume.
FLUID SLIP - Commonly used to describe the migration of liquid around
the internal moving parts of a pump. It is the volumetric difference
between physical component displacement and liquid throughput of a
pump system.
FLUID SLIP LOSS - Refers to the liquid which passes through the
clearance space, (~.00005") between the piston and the cylinder wall.
The clearance between the piston and cylinder wall must be optimized
for the liquid being pumped in order to minimize the loss due to
fluid slip.
GLAND - Provides for washing the rear portion of the piston by a
liquid passing at a rate of ~2 to 5 ml/min through a groove in the
cylinder wall. The gland prevents the liquid being dispensed from
accumulating at the rear of the piston, thereby greatly reducing the
possibility of a seized pump.
HALL EFFECT - In a current-carrying semiconductor bar located in a
magnetic field that is perpendicular to the direction of the current,
the production of a voltage perpendicular to both the current and the
magnetic field. This physical effect is used in position sensors.
HARDNESS - 1) The relative resistance of a mineral to scratching, as
measured by the Mohs' scale. 2) The relative resistance of a metal to
denting, scratching or bending.
HARDWIRED SIGNALS - Electrical signals between two control devices
connected with dedicated conductors.
INTERFACE - 1) A point or device at which a transition between media,
power levels or modes of operation is made. 2) The hardware and
signal specifications for linking two units of electronic equipment.
LED INDICATORS - Light Emitting Diodes. Utilized as system condition
or mode indicators and warnings.
LINEAR MOVEMENT - Movement along a straight line.
LINEAR RATE - Rate of the linear component of a movement.
2000 SERIES SYSTEM - One of two major types of precision liquid dispensing or metering systems available from IVEK Corporation. The controller of the linear system can separately command the linear (displacement) and rotary (valving) motions of the piston. The liquid displacement is constant over time, limited by acceleration and deceleration at the beginning and end of the motion. The Digispense 2000 and Multispense 2000 are linear systems.
LOAD MODE - Linear controller mode used to load the pump cylinder
when empty or when the volume is less than the next volume of liquid
required to dispense or meter. The automatic load function can be set
to Manual, Empty, or Every.
LOAD RATE - The pumping rate, of a linear system, during the load cycle in microliters per second, (ml/s). The same controller setting is used for loading and priming.
MECHANICAL VALVING - Valve ports are opened and closed via mechanical
actuation. This is in contrast to check valves which open and close
as a result of fluid pressure/flow.
METER MODE - Controller mode function used for continuous pumping of liquid. METER is very similar to PRIME. The difference between the two is PRIME gets the system setup for dispensing or metering of liquid and METER is used for constant flow, liquid metering.
MICROMETER - Rotary Pumps, (B, C and D sizes); An optional micrometer
scale assembly mounted to the Motor/Base Module. Used for position
finding or fine adjustment and not for gross pump head movement.
MOTOR/BASE MODULE - The module in a rotary system that drives the
piston in the attached Pump Module. The Motor/Base Module produces a
combined rotary and linear movement that synchronizes the liquid
displacement and valving functions. The module consists of a motor,
spindle, spindle sensor, base frame and adjusting mount for the Pump
Module.
MULTIPLEX SYSTEM - The Multiplex system uses a single motor and two
lead-screws to drive multiple three-piece pump modules. The motor and
lead-screw combination drive the pistons in a linear motion to create
displacement. Each Pump Module has an air driven rotary actuator to
turn the valve towards the intake or discharge port. (Click to see
animation)
NOISE - Any unwanted disturbance within a dynamic electrical or
mechanical system. This can include electrical, electromagnetic, or
acoustical energy.
OPERATING PARAMETERS - 1) All specified values utilized during system
operation in order to achieve the desired performance of the system.
2) The system controller values regarding volume, rate and direction,
or Pump Module displacement setting, or controller settings for
motion control devices incorporated with the system.
OPTICALLY ISOLATED SIGNAL - Signals that are coupled using a device that connects signals from one electronic circuit to another by means of light. More correctly, the signals are electrically isolated and optically coupled between the two circuits.
PISTON - Pump Module component. Part of the piston/cylinder set.
PNEUMATIC - Actuated or operated by compressed air or other gas.
PORTS - Openings in the Pump Module cylinder and housing allowing the flow of liquid through the Pump Module assembly during operation.
PRIME MODE - Used for filling the pump liquid circuit, (inlet tubing, pump chamber, outlet tubing), at initial start-up. Also for eliminating air bubbles in the circuit.
PRIME RATE - Motor speed during a prime operation. In a linear system, the prime rate and the load rate use the same setting. In a rotary system, the prime rate may be the same as the dispensing rate, or a separate setting may be used.
PULSATIONS - Cyclical fluctuations of liquid flow.
PULSE DAMPER or PULSE SUPPRESSOR - Mechanical device inserted into
the outlet tubing of the liquid circuit to dampen liquid pulsations.
PUMP MODULE - Liquid management system assembly consisting of the precision ceramic piston/cylinder set, protective housing, mounting hardware and fittings.
PUMP SEIZED - An event whereby the ceramic piston and cylinder set become locked or "frozen" together.
REFERENCE CYCLE - In a linear system, an operational cycle during
which the controller determines the absolute linear and rotary
position of the linear actuator. After the power is turned on, or
after a fault, a reference cycle must be completed before any other
operation of the linear actuator can take place.
ROTARY MOVEMENT - The motion, (rotation) of a part or device around an axis.
ROTARY SYSTEM - One of two major types of precision liquid dispensing
or metering systems available from IVEK Corporation. The rotary
system has a single mechanical coupling which translates the rotation
of the motor into the combined linear (displacement) and rotary
(valving) motions of the piston. The angular adjustment of the Pump
Module determines the piston displacement for each dispense cycle.
The controller does not have separate control of the linear and
rotary motions of the piston. Liquid displacement is sinusoidal and
corresponds to one rotation of the motor shaft (half is zero flow and
half is 50% of sinusoid). The Digispense 700, Digispense 800,
Multispense 900 and Multispense are rotary systems.
ROTARY VALVE - A device in which the rotation of a part performs the
valving function.
SANITARY PUMP - Pump Module option designed to conform to the
cleansing standards of the US Food and Drug Administration.
SELF PRIMING - A pump which requires no pre-wetting or pressurization procedure before being able to initiate liquid flow.
SPECIFIC GRAVITY - The ratio of the density of a fluid to the density of water. The specific gravity of a fluid must be considered when making gravimetric measurements (weighing) of the output of a volumetric pump.
SPINDLE - Component in the Motor/Base Module of a rotary system, which couples the motor shaft to the piston. The spindle contains a spherical bearing which accepts the piston drive pin.
STEPPER MOTOR - A digital device that converts electrical pulses into
proportionate mechanical movement. Each revolution of the motor shaft
is made in a series of discrete identical steps. The design of the
motor usually provides for clockwise and(or) counterclockwise
rotation.
TORQUE - A force that tends to produce rotation or twisting.
TORQUE LIMITED DRIVE - Motor function that will preclude piston
breakage by causing the motor to stall in the event of a pump seizure.
TOTALIZER - Controller option displaying total motor turns or
dispense triggers.
VALVING - Selectively opening the liquid path between the pumping
chamber and one of the liquid ports.
VALVING OPERATION - Rotating the piston in a linear system to change the port communicating with the pumping chamber without displacing liquid.
VALVING SPEED - The rotational speed during valving in a linear system.
VARIABLE DISPLACEMENT - Capability of changing the volume of liquid moved by the piston for each stroke through either electrical or mechanical means.
VISCOSITY - The measure of a fluid's tendency to resist a shearing
force. The viscosity of a fluid affects the degree to which it
resists flow under an applied force. Viscosity can remain constant,
increase, or decrease as shear rate (flow rate) increases. Absolute
viscosity is generally measured in centipoise. Kinematic viscosity
includes the influence of the specific gravity of the fluid and is
generally measured in centistokes.
Kinematic Viscosity X Specific Gravity = Absolute Viscosity
WET OPERATIONS - Refers to the operation of the liquid management
system. It is preferable to avoid running the pump dry. For extended
periods, most application liquids will provide the necessary
lubrication and cooling to prevent chirping, binding or seizure. |