Technical Manual
FT420
– Iss 2.4
59
While
L
MAX
- the maximum cable length,
V
LOWEST
- the lowest power supply voltage.
V
WORKING
- the minimum working voltage of the output device,
I
MAX
- the maximum current,
R
RPM
- the real resistance per metre.
For power outputs, the lowest voltage of the CIE power supply is fixed at 22V. For the MDH output,
the lowest power supply voltage is determined by the MDH specifications.
For example,
Assume that the lowest power supply voltage is 22V. The minimum working voltage of a device is 18V
with a maximum current at 0.5A and a real cable resistance of 0.04
Ω/m. The calculated maximum
cable length will be (22 - 18) / (0.04 x 0.5) = 200 metres.
3.13.5 Requirements and Reference cable types
The requirements and the referenced cable specifications in Table 40 are used to achieve the
specified maximum cable lengths corresponding to each connection type, equivalent or better type of
the cables shall be used.
Table 40 Cable Types for Different Connections
Connection
Requirement
Reference Cable Specifications
Maximum Cable Length
Zone Circuits
Use Equation 1
Two core, Red, 1mm
2
conductive area,
Specified cable resistance 0.02 Ohms / m
Real cable Resistance 0.04 Ohms / m
1250 meters
Power Outputs
Use Equation 2
Two core, Red, 1.5mm
2
conductive area
Specified cable resistance 0.0128 Ohms/ m.
Real cable Resistance 0.0256 Ohms / m
781 meters with the maximum
current of 0.5A and the lowest
voltage of 12V.
Supervised
Control Outputs
Use Equation 2
Two core, Red, 1.5mm
2
conductive area
Specified cable resistance 0.0128 Ohms/ m.
Real cable Resistance 0.0256 Ohms / m
156 meters with up to 1A current and
the lowest voltage of 18V
MDH Control
Output
Use Equation 2
Two core, Red, 1.5mm
2
conductive area
Specified cable resistance 0.0128 Ohms/ m.
Real cable Resistance 0.0256 Ohms / m
78 meters with up to 2A current, the
minimum working voltage of 18V,
and the lowest power supply of 22V
Audio MIC Input
Shielded twisted pair audio cable
100 meters
Содержание Firetracker FT420
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Страница 76: ...Technical Manual FT420 Iss 2 4 76 6 3 FT420 Block Wiring Diagram Figure 39 FT420 with All Options ...
Страница 77: ...Technical Manual FT420 Iss 2 4 77 Figure 40 FT420 with Gas Kit Interface ...