Print Date 12/05/15 Page 18 of 32 S7600-00MA-08
2.3 SETTING UP PROCEDURES
2.3.1 Fuses
If any problems occur after the Transmitter has been installed and switched on, fuses may need to be
checked and possibly replaced. However, a blown or open-circuit resettable fuse would generally
indicate the presence of a fault, which would need correcting.
The type, function and access to fuses is as follows :
Type
Function
Access
500mA (F) Fuses
(for smd holders,
‘Littelfuse’
R451.500)
One per E2021.
For protection of control circuits
within E2021 Amplifier modules.
If fuse blows, all front panel
displays on just the affected E2021
go out and its power level falls.
Remove Amplifier module from front,
taking care to release the mechanical
securing locks first. Smd fuseholder is at
rear of unit under the screen cover.
500mA (F) Fuse
(for smd holders,
‘Littelfuse’
R451.500)
One only.
For protection of control circuits
within E2025 Combiner Unit
If fuse blows, all front panel
displays on just the E2025 go out
and the overall output power level
falls to zero.
Note, if a spare fuse is not
available, one may be transferred
from one of the E2021 modules to
enable operation at lower power.
Slide Combiner Unit forwards after
removing front and single rear fixing
screws, taking care not to strain any
leads connected to its rear. Remove
front screen cover section.
Smd
fuseholder
is
accessible
underneath the screen cover on the
front printed circuit board, right hand
side.
! CAUTION ! Ensure that the front
panel
Supply
Disconnector
is
switched to ‘off’ (i.e. at O) and is
preferably padlocked in that position.
16A (T) HBC
5x32mm
(¼ x1¼ in) Fuses
One per E2021.
For protection of internal dc supply
leads to and high current circuitry
within E2021 Amplifier modules.
If fuse blows, all front panel
displays on just the affected E2021
go out and its power level falls to
zero.
At the bottom rear of the Transmitter,
the larger fuse-holders grouped in ones,
twos or fours on the left/right hand sides.
Note FS number and position mirrors
amplifier number and position.
! CAUTION ! these are high energy
circuits and thus care must be taken
if replacing the fuse with power on.
6.3A (T) HBC
5x20mm Fuses
Two only.
For protection of internal low
current dc supply leads.
Internal low current supplies are
dual redundant, thus the loss of one
fuse produces no failure (only
E2023 display warning). If both
blow, E2023, E2024 and E2025
front panel displays all go out and
the overall output power level falls.
At the bottom rear of the Transmitter,
the single smaller fuseholders on the left
and right hand sides, FS9/10.
! CAUTION ! these are high energy
circuits and thus care must be taken
if replacing the fuse with power on.
6.3A (T) HBC
5x20mm Fuses
Two only
For protection of mains supply
leads and circuitry intended for
connection to Exciter/Drive(s).
At the bottom rear of the Transmitter,
the single smaller fuseholders adjacent
to the associated mains output sockets.
FS11/12
! CAUTION ! these are high energy
circuits and thus care must be taken
if replacing the fuse with power on.
