IBM System/370 145 Reference Summary page 103

CE1 POWER ON
CE2 CK RESET
ERROR
OVERRIDE
I
NORMAL
CEJ BLOWER OFF
MG HOLD
MG PWR OFF
CONTROLLED
NORMAL
POWER OFF
CE5 1/0 HOLD
NORMAL
I/DOFF
CE6 LAMP TEST
REG TEST
NORMAL
Performs the same h.mct1on as the console power-on key (m1t1ates a power-on sequence)
This 1s a momentary pos1t1on of switch CE2 that resets the power check c1rcu1ts
ip1cks K 12) The power check c1rcu1ts must be reset after each power malfunction
before power can be reapplied to the system
Bypasses all malfunctions that cause a power-check concllt1on by prov1d1ng a
return path for relay, K12 The power-check conditions bypassed are thermal
trip, undetvoltage dete<:t, CB trip, and MG check This posmon of CE2 switch
can be used as a trouble shooting aid by enabhng power turn-on under a power
check cond1t1on. By using the error override capability along with CE6 switch
(REG TEST pos1t1on) when a CB trip 1s apparent, maintenance personnel can
monitor the regulator sequence lights and hnd which regulatorls) are not
supplying proper output voltages When the switch 1s at ERROR OVERRIDE,
the CE panel power check light 1s lit and the console POWER check hght 1s lit
to 1nd1cate that a CE switch 1s at a test mode position
Allows the power che<::k c1rcu1ts to function
in
their normal manner. CE2
switch should be maintained at this pos11ton during normal running operations
Enables turning off the blowers prematurely after a power-down sequence
has been started (The blowers normally operate for five minutes after
powering-down the system )
Keeps the MG set running after the system has been powered down (Bypasses the
wstem power-off switch control over the MG set ~
Allows the MG to be turned off with the system when the power-off switch
1sact1vated
Allows the power on switches to control system power m the regular manner
CE4 switch must be at NORMAL m order for the system to operate
Performs the same function as the console powerOoff key lmt1tiates a power off sequenct1
Oiasables the operation of OOth the console power on and CE panel
power on switches Anytime the CE 4 switch 1s at POWER OFF. the
console power check light 1s lit This switch can be used to prevent power
from being applied to the system while 11 Is being serviced
Allows the 24V de control to the 1/0 umts to be maintained after the
system is powered-down Anytime CE5 switch 1s at 1/0 HOLD, the CE panel
power check 11gh1 1s lit and the console power hght 1s turned on.
Allows the 1/0 dev1ccs turn-on procedure to function under control of the system
power-on operation CE5 switch should be kept at NORMAL for all regular
operations
lnh1b1ts the turn-on of 1/0 d11111ces over the channel. Anytime CE5 is at 1/0 OFF,
the power-on complete light does not hght If CE5 1s switched to 1/0 OFF after
power-on 1s complete, the channel 1/0s w11I drop and the power-on complete light
will turn off To bnng the I/Os up agam, press POWER OFF, then POWER ON
Causes all CE panel hghts to glow The CE6 switch can be operated to LAMP
TEST at any time without affecttng system operation
Provides a means for checking all regulators outputs by means of the regulator
sequencing ltghts If a CB power check 1s 1nchcated, one can u~e the CE2 switch m
the ERROR OVERRIDE pos1t1on along with REG TEST and detect the regulator(s)
that are not providing the indicated output (Associated regulator 1nd1cator 1s off
J
Provides no function CE6 switch should be kept at NORMAL durmg al! regular
system operations
9.1