ESPRIT Gas Extinguishing User Manual
INSTALLATION
26
Approved Document Ref: UI-ESG-01 Issue 2.0
Solenoid Actuators
A Back-EMF diode must be fitted across the solenoid coil. Observe polarity
–
see diagram below. Coil
resistance 25Ω
-
200Ω.
Maximum line impedance 1.5Ω
-
5.0Ω depending on coil impedance –
see calculation below.
Two solenoids can be connected in parallel. The panel will learn the combined circuit impedance and
will indicate an open circuit condition if one of the actuators becomes disconnected.
Solenoid Actuator Circuit Lengths
The voltage drop on the actuator circuit should be calculated to ensure that the voltage at the end of
the circuit exceeds the minimum required by the solenoid (typically 18V) when the actuator circuit has
minimum output voltage value.
The voltage at the end of the circuit is given by:
•
Minimum Actuator Voltage = VOUT(MIN)
–
(IACTUATOR x RCABLE)
•
Minimum Output Voltage (V
OUT(MIN)
) = V
BAT(MIN)
–
1.5V = 19.5V
•
Actuator Current (I
ACTUATOR
) is the sum of the loads presented by the actuator devices.
•
Cable Resistance (R
CABLE
) is the sum of the cable resistance in both cores x cable length.
•
Cable Resistance (R
CABLE
) for 1.0mm
2
is 0.036Ω / metre
•
Cable Resistance (R
CABLE
) for 1.5mm
2
is 0.024Ω / metre
•
Cable Resistance (R
CABLE
) for 2.5mm
2
is 0.015Ω / metre
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