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12-8
IM 704610-01E
Explanation
If a problem is discovered during the diagnostic test (self test), contact the dealer from
which you purchased the instrument for repairs.
Signal Cables
When performing the self test, remove all cables connected to the instrument (both input
and output) other than the power cable and communication cable. Also, the self test
cannot be performed if the TA220 is in remote mode. Switch from remote mode to local
mode.
Display and Indicator Test
You can test all indicators on the instrument including the 7-segment LED and decimal
point of Display 1, and the dot pattern of Display 2. However, the indicators for the
measurement input terminal (RF input) cannot be tested. Turn the rotary knob and
confirm that the lit position of the indicator moves accordingly. If all displays and
indicators (excluding the measurement input terminal indicator) illuminate in order, they
are functioning normally.
Key and Rotary Knob Test
When you press a key or turn the rotary knob, the corresponding characters are
displayed in Display 2. If the words/characters indicated in the table below are
displayed, the key or rotary knob is operating normally.
Key/Rotary Knob
Words/Characters Displayed in Display 2
MEDIA
Media
FUNCTION
Function
ARMING
Arming
INHIBIT
Inhibit
SHIFT
Shift
LOCAL
Local
RECALL
Recall
ENTER
Enter
POLARITY
Polarity
TRIG
Trig
IMPEDANCE
Impedanc
EQUALIZER
Equalize
<
Left
>
Right
MEASURE
Measure
SCALE
Scale
Rotary knob turned right
JogRight
Rotary knob turned left
JogLeft
Meter Test
If the values displayed in Display 1 increase or decrease, and the needle moves to the
left or right as you turn the rotary knob to the left or right, the meters are functioning
normally.
Board Test
You can test the CPU board, measure board, input board, equalizer board, and Ethernet
board. If PASS is displayed, the board is operating normally. If a problem is detected, a
hexadecimal value indicating the problem can be displayed separately for each board.
When contacting your nearest YOKOGAWA dealer for repairs, please give them that
hexadecimal number.
12.4 Self Diagnostics (Self Test)