Federal Signal G-SND Instructions page 9

Preparing to Wire the Ex de Increased Safety Models
SHOCK HAZARD - To avoid electrical shock hazards, do not connect wires when power is applied. Failure to observe this
warning may lead to serious injury or death.
This section has wiring instructions for the three increased safety models:
• G-SND 24 Vdc
• G-SND 120 Vac
• G-SND 240 Vac
Ex de units are supplied with a six-pole, spring-tension clamp style terminal block. The maximum wire gauge is 4.0 mm
(12 AWG). The wire must be rated 85°C or higher. Use only stranded cable to terminate the sounder. The cross-sectional
area of the primary earth (ground) must equal the cross-sectional area of the phase conductor.
Cable termination should be in accordance with specifications applying to the application. It is recommended that all
cables and cores be fully identified. Use the appropriate cable gland for the application. Gland entry threads are M20-1.5
6H.
Conductive metalwork, including cable glands, must be a minimum of 5 mm away from the terminals.
Leads connected to the terminals shall be insulated for the appropriate voltage, and this insulation shall extend to within
1 mm of the metal of the terminal throat.
The G-SND terminal block is supplied with two conductors per pole. The terminal block allows for easy supply-in and
loop-out wiring to connect sounders in series.
Tools needed:
• 3.0 mm A/F hexagon key
• No. 1 Phillips screwdriver
• Wire stripper
Wiring the Ex de Models
CIRCUIT BOARD DAMAGE - The DC sounders are polarity sensitive and MAY BE DAMAGED by incorrect electrical
hookup. When connecting the DC sounder to the voltage supply lines, POLARITY MUST BE OBSERVED. In addition,
damage will result if the voltage rating of the particular model is exceeded by more than 10 percent.
To wire the Ex de models:
1. Unscrew the four M4 socket-head cap screws and remove the terminal box cover.
2. Strip the wire insulation 8 mm to 9 mm (0.33 in).
NOTE: When using more than one single or multiple strand lead, the connection into either side of any terminal
must be joined in a suitable manner, e.g., two conductors into a single insulated crimped bootlace ferrule.
3. To connect wires, press the button on the terminal block with a Phillips screwdriver and insert the wire into the
round opening. Release the button to make the connection.
4. Follow the instructions starting below for your line voltage and continue to Step 5 on page 8. Refer to Figure 6 on
page 6 for the voltage selector switch and the tone chart on page 8.
Federal Signal signaling.fedsig.com
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