To Next Page

To Previous Page

1. Turn off the power and unplug the instru-

ment. Remove the instrument cover and

the head cover. Place an empty sample

tube in the sample well.

2. Manually push the head all the way down

until the head stop screw (A) meets the

base of the deck (B).

3. The head position sensors are located on

the head sensor board. To adjust the head

sensor position, use an Allen wrench and

loosen the two bracket screws (C), and

move the board (D) and bracket (E) either

up or down until the head sensor flag (F)

is in the middle of the head down sensor

(G).

Note: To facilitate access to the two bracket

screws (C), loosen and move the print-

er bracket assembly.

Note: Your instrument is equipped with a

series of diagnostic LEDs on the main

application board PCB605 to allow

visual identification of drive signals

and sensor activation.

• The yellow LEDs marked “Drive

Up” and “Drive Dn” indicate that

the control electronics have issued a

command to the head motor relays.

• The red LEDs marked “Head Up”

and “Head Dn” indicate that the

corresponding optical sensor has

been tripped.

Head Sensor Adjustment

The Advanced

Model 3250/4250 Service Manual

Advanced Instruments 4250 User Manual

Questions and Answers: