Bio-Rad CHEF-DR® III Variable Angle System - Manual (Page 10)

If the system includes the Cooling Module, connect the temperature probe cable to the
REMOTE SENSOR port on the rear panel of the Cooling Module. Insert the other end of the
temperature probe cable into the rear of the electrophoresis chamber.
Establish the correct buffer flow before attempting any electrophoresis runs. The opti-
mal flow rate of buffer through the electrophoresis chamber is approximately 0.8–1 liter per
minute (approximately 70 on the pump). When the correct flow rate has been achieved, use
that pump setting for all subsequent electrophoresis runs. Fill the chamber with 2.2 liters of
buffer. Turn on the pump and measure the flow of buffer at the drain port by removing the
clamp from the 6" piece of tubing. Make adjustments to the buffer flow with the pump.
It is beneficial to fine tune the chiller before attempting any electrophoresis runs. Turn on
the chiller and pump approximately 1 ⁄
2
hour before adjusting the temperature. Initially, it will
be necessary to fine tune the temperature setting to achieve a consistent running temperature.
2.3 CHEF-DR III Operation
This section describes general operation. See Sections 3 and 4 for sample preparation,
gel casting, gel running, and staining.
Power Up
The CHEF-DR III front panel display is divided into two sections (see Figure 2.3.). On
the left are, BLOCK, INITIAL SWITCH TIME, FINAL SWITCH TIME, RUN TIME, and
RAISE and LOWER keys. On the right are VOLTS/CM, INCLUDED ANGLE, ACTUAL
CURRENT, PAUSE/START RUN, and RAISE and LOWER keys. At power up, the left dis-
play will show 1 with BLOCK lit, indicating Block 1 is active. The right display will show
OFF. The program parameters will be at the default setting or those last set before the power
was turned off, since the battery back-up RAM stores the last program entered. If a program
was in progress or in PAUSE, the run parameters will be retained and the PAUSE mode will
be active (flashing PAUSE light).
Fig. 2.2. Front panel display of the CHEF-DR III system.
Parameter Entry
The CHEF-DR III system has the flexibility of using up to three separate, consecutively
executing Blocks. Each Block has the run parameters of Initial Switch Time, Final Switch Time,
Run Time, Volts/cm, and Included Angle. During a run, Block 1 is run first, then Block 2, then
Block 3. To enter run parameters into Block 1, press BLOCK. The left display should show 1,
indicating Block 1. If not, press RAISE or LOWER on the left side of the display panel until 1
is shown. Enter the Initial Switch Time, Final Switch Time, and Run Time with the RAISE and
LOWER keys on the left side of the display panel. Enter the Volts/cm, and Included Angle with
the RAISE and LOWER keys on the right side of the display panel. If more than 1 Block is
needed, then press BLOCK and go to Block 2 by pressing RAISE. The left display will show
the number 2, indicating Block 2. Continue entering the run parameters as in Block 1. If a third
Block is needed, press BLOCK, go to Block 3 by pressing RAISE, then continue entering the
run parameters as in Block 1. Below are the limits for each of the run parameters.
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