Jands Event 4, Техническое руководство

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Circuit Notes 3 - 1
Revision 1 - 07 July
1999
Event 4 TECHNICAL MANUAL
6. Switch off console.
7. Remove shunt across J1
This procedure should be performed whenever either a new CPU or PSU is installed.
3.1.3 Battery
The lithium battery should last approximately 5 years from the date the battery was
made - note that a 4 year life from date of product sale would not be unexpected when
delivery and manufacturing times are allowed for. The battery should be considered
flat if its terminal voltage measures below 2.9 volts. Backup any required show data to
diskette before the battery is replaced.
CAUTION
Danger of explosion if battery is incorrectly replaced.
Replace only with the same or equivalent type
recommended by the battery manufacturer. Dispose of
used batteries according to the battery manufacturer’s
instructions.
3.1.4 Logic
The logic requirements for the board are contained in two logic devices, IC33 and
IC53. These are in circuit programmable, and are programmed by connecting an
appropriate header to CONN3. If it is necessary to reprogram these devices in the
field, follow the instructions supplied with the kit.
3.1.5 Desk Lamp Dimmer
The desk lamp dimmer circuit consists of a PWM switching circuit protected by a
PTC polyswitch. The polyswitch will trip under overload conditions – when it does
LED L6 will extinguish. Due to the nature of the polyswitch it is necessary to either
disconnect all desk lamps or switch the console off for approximately one minute in
order for it to reset.
3.1.6 DMX Outputs
The DMX outputs are not opto-isolated, however a protection network decouples the
driver ICs from high voltages which may be applied during external mains faults.
After a fault has been removed these devices take approximately one minute to reset,
and during this time the output cables should be disconnected or the console switched
off.
3.1.7 Keyboard
The console is protected against excessive load current through the keyboard
connector by a polyswitch. After a fault has been removed this device takes
approximately one minute to reset, and during this time the keyboard should be
disconnected or the console switched off.