CCS800 | Service manual | Chapter 7 | Diagnostics and faultfinding en | 37
Bosch Security Systems | 2005-01| 3922 880 21112
7.5 Measuring instructions for the Delegate and Chairman unit
How to check if a Delegate or Chairman unit operates correct is described in the next paragraphs. Supply current
7.5.1 Supply current.
7.5.2 Internal supply voltages.
7.5.3 Unit presence.
7.5.4 Unit type.
7.5.5 Microphone switch and light-ring.
7.5.6 Internal signals for Delegate and Chairman units.
7.5.7 Internal signals only for Delegate Units.
7.5.8 Chairman Only mode.
Before you start measuring:
• Connect a Delegate and/or a Chairman unit to the CPSU.
• Turn the volume control (R54) of all Delegate and Chairman units in the maximum clockwise position (volume
maximum).
• Put the mode switch on the CPSU in the OPEN mode (1,2,3 or 4).
• Disconnect the loudspeaker from the Delegate or Chairman unit and connect a resistor of 25 ohm between pin 1 and
2 of X5.
Use the diagrams (chapters 13.12 and 13.14) to locate the measurement points (chapter 13.11) and components mentioned
in the measurement instructions.
7.5.1 Supply current
Measure the supply current from V+ by means of a current meter in the power supply line. This should be between 12mA
and 22mA
7.5.2 Internal supply voltages
Measure the internal supplies on the Units itself of +15V via M15 and +5V via M12, both related to M2 (= internal 0V):
a) at M15 this should be: +15V ± 750mV
b) at M12 this should be: + 5V ± 250mV
Note: From Data book, the IC itself is specified as ± 250mV
7.5.3 Unit presence
To detect the presence of a unit, measure the voltage via M101 related to M8 (= internal 0V).
> 4.5 V ±50mV = unit present.
7.5.4 Unit type
To detect the presence of a Delegate or Chairman unit, measure the voltage via M100 related to M8.
< 0.5V ±50mV = Chairman Unit
> 4.5V ±50mV = Delegate Unit
7.5.5 Microphone switch and light-ring
Press the microphone button on the Delegate/Chairman Unit.
The Light-ring must lit now (M70 related to M8 (0V) should be between 7.0V and 9.0V)
7.5.6 Internal signals for Delegate and Chairman units
7.5.6.1 Power reset
Connect an external adjustable power supply (10-24V) instead of the
CPSU power supply connected to X1 (see figure of X1)
V+ related to M2 (GND) is successively +15V and 12.8V.
Measure the Power-reset voltage via M14 of the Delegate or Chairman
Unit, related to M8 (0V).
X1 trunk connector on Delegate/ Chairman board.
V+ M14
+15V < 1V
+12.8V > 4V (Power-reset activated)
Increase the power supply V+ back to +20V.
To Next Page
Loading...
Need help?
General
