Thermo Scientific 11174729, Instruction Manual

Page: 7 / 66

Chapter 1
USE AND FUNCTION
Thermo Fisher Scientific MR23i 1-1
Chapter 1
USE AND FUNCTION
DESCRIPTION
The Jouan MR23i is a high speed centrifuge (23 000 rpm) desi-
gned to separate substances by elevated centrifugal acceleration.
It is equally suited to precise, low speed operation.
Different rotors can be fitted to the drive in order to match the sam-
ple containers and the required performance. The maximum speed
(and, by consequence, the resultant centrifugal force) is a function
of the rotor in use.
A control system permits the speed, acceleration and braking
rates, run time and temperature to be monitored and controlled.
Refrigeration is assured by a refrigerant group charged with a
CFC-free fluid. The refrigerant fluid circulates around the chamber
to achieve maximum efficiency.
RELATIVE
CENTRIFUGAL
FORCE
Suspended solids are separated by the Relative Centrifugal Force
(RCF) applied to the sample. The effective force increases with the
square of the speed of rotation and the distance from the axis of
rotation.
The following formulae permit the calculation of primary parame-
ters and of transformations relating to changes in primary parame-
ters.
Note The value introduced for the radius can be adjusted to allow for posi-
tion within the tube such as at a boundary. Maximum radii are quoted
in the specifications tables (chapter 3).
Centrifugation
formulae
Note To calculate actual results, press the keys on a pocket calculator in
the order shown.
R radius (in millimetres)
N speed (in r.p.m.) ÷ 1000
RCF gravitational acceleration ‘g’
M+ add to memory
MR memory recall