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MAN0530 Issue 09 October 03 Searchline Excel
2104M0506
3. INSTALLATION AND OPERATION
3.4 POWER SUPPLY
3.4.1 General
The Searchline Excel gas detector is designed to be operated from a nominal 24V DC supply.
The supply voltage at the terminals must be within the range 18 to 32V.
The unit maximum power consumption and cable lengths are as follows:
Maximum Power Maximum Cable Length Maximum Cable Length
Consumption (W) (m) with 1.5mm
2
(m) with 2.5mm
2
Unit Type Conductors (12 ohms/km) Conductors (7.6 ohms/km)
Receiver (All ranges) 8 550 900
SR Transmitter, 5 900 1,400
(Turbo heating enabled)
SR Transmitter, 3.5 1,300 2.000
(Turbo heating disabled)
MR/LR Transmitter, 7.5 600 950
(Turbo heating enabled)
MR/LR Transmitter, 5.5 820 1,300
(Turbo heating disabled)
Notes:
1. Control room supply voltage assumed to be +24V.
2. Standard configuration of the Transmitter is with turbo heating enabled.
Terminal sizes: DVC-100 0.5mm
2
- 4mm
2
(20AWG - 12AWG)
DX-100/DX100 (M) 0.5mm
2
- 4mm
2
(20AWG - 12AWG)
PL612 0.5mm
2
- 6mm
2
(20AWG - 10AWG)
3.4.2 Power Supply Connections - Turbo heating Disabled
When connected as shown in section 3.3.4 Transmitter Connections all ranges of Transmitter
have turbo heating mode enabled.
This means that during conditions of low ambient temperature, additional heating power is
applied to the unit s window to minimise condensation, frosting and snow buildup.
If the application/installation does not require turbo heating, reduced power consumption can
be achieved by disabling this mode.
The turbo heating is disabled by reversing the power supply connections to the Transmitter as
shown in the following diagram. All other connections remain the same.