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INTEGRUS | Digital Infra-red Language Distribution System
BOSCH Security Systems B.V.| February 2003
Figure 1.27 and Table 1.2 illustrate the calculation of the signal delays and the delay switch positions.
584 ns
350 ns
563 ns
339 ns
R2
R5
R4
237 ns
R1
R3
Figure 1.27 System with five radiators and measured impulse response times
Table 1.2 Calculation of the delay switch positions of a system with one transmitter
Radiator
number
Impulse response
time [ns]
Cable signal
delay [ns]
Signal delay
difference [ns]
Delay switch
position
1
350
350/2 = 175
292
-175 = 117
117/33 = 3.54 = 4
2 584
584/2
=
292
292
-292 = 0
0/33 = 0
3
237
237/2 = 118
292
-118 = 174
174/33 = 5.27 = 5
4
339
339/2 = 169
292
-169 = 123
123/33 = 3.73 = 4
5
563
573/2 = 281
292
-281 = 11
11/33 = 0.33 = 0
The calculated delay switch positions based on impulse response time can differ from the calculated delay switch positions based on
cable lengths. This is caused by the accuracy of the measurements and the accuracy of the cable signal delay factor per meter as specified by the
manufacturer of the cable. If the impulse response time is measured correctly, the calculated delay switch positions will be the most accurate
1.5.2 System with two or more transmitters in one room
When radiators in one multi purpose room are connected to two transmitters, an extra signal delay is added by:
N
Transmission from master transmitter to slave transmitter (cable signal delay).
N
Transmission through the slave transmitter.
Use the following procedure to determine the delay switch positions in a master-slave configuration:
1. Calculate the cable signal delay for each radiator, using the procedures for a system with one transmitter.
2. Calculate the signal delay of the cable between the master and the slave transmitter in the same way as for cables between a
transmitter and a radiator.
3. Add to the cable signal delay of the cable between the master and the slave, the delay of the slave transmitter itself: 33 ns.
This gives the master-to-slave signal delay.
4. Add the master-to-slave signal delay to each radiator connected to the slave transmitter.
5. Determine the maximum signal delay.
6. Calculate for each radiator the signal delay difference with the maximum signal delay.
7. Divide the signal delay difference by 33. The rounded off figure is the signal delay switch position for that radiator.
8. Add delay switch positions to radiators under a balcony, if applicable (see section 1.5.3)
9. Set the delay switches to the calculated delay switch positions.
: Turn the delay switches carefully to a new position until you feel that it clicks into position, to prevent that a switch is positioned
between two numbers, which would result in a wrong delay setting.
: When a master-slave configuration is used for rooms which are always separated, the delay switch positions can be determined per
system and the delay caused by transmission from master to slave transmitter can be ignored.
Figure 1.28, Table 1.1, Table 1.3 and Table 1.4 illustrate the calculation of the extra master-slave signal delay.
