Honeywell 6000 Series Reference Manual page 51

Table 3-2 (cont). DSU19O Controls and Indicators
CONTROL OR INDICATOR FUNCT ION
Unit Number Indicator
SELECT LOCK switch/
indicator
' LOCAL indicator
TEMP indicator
WRITE PROTECT switch/
indicator
Lights when the heads are loaded, indicating which unit is
online. Unit numbers are installed by installation personnel
and should not be changed.
Lights when one or more of the following fault conditions
occur:
1. Read or Write is. selected without an On Cylinder signal
'2 Low voltage (isv. izov, or -16V) signal
3. Read and .W'rite are selected at the same time
4 Servo digits lost for more than 200 milliseconds (heads
automatically unload)
5. More than one head is selected
6. Head Register contains number exceeding 18 (No Head
Select) '
7. Write command without write current
8. _ Write current without Write command
9. Write current 'Without write data
Conditions 5 through 9 are known as current faults. They
are inhibited while writing address marks.
All conditions require that the SELECT LOCK switch be
pressed or that the controller. iSSue a DIN.
Lights when drive experiences either of the following
conditions:
1. Controller issues an SLS command.
2. ONLINE switch on logic chassis maintenance panel
set to either OFFLINE position.
Lights when air flow is restricted enough to cause potential
overheating. If air flow is less than about 150 fpm past
either switch, indicator will light. One switch is located
next to the intake of the logic fan that cools +5V regulator.
The second switch is located at the intake of the power
supply fan that cools the power amplifier board.
Inhibits all write Ioperations. Any subsequent WRT or WRT
TEST command will set State Violation (DSBl, Bit 23).
3—6 DB37'