Filter
Top Products
46 ST 3000 Release 300 and SFC Model STS103 User’s Manual 6/08
4.4 Wiring ST 3000 Transmitter, Continued
Approval body
requirements
If your transmitter was ordered with Table III option 3N for self-
declared approval per 94/9/EC (ATEX4), you must use a power supply
that includes a voltage limiting device that will keep the voltage to the
transmitter from exceeding 42 Vdc. You can achieve this by using a
battery as the supply or one of these voltage limiting means.
• Double wound mains transformer per BS 3535 or equivalent.
• An adequately rated zener diode whose voltage is not significantly
higher than the rated voltage.
• An adequately rated semiconductor voltage regulator.
Lightning protection
When your transmitter is equipped with optional lightning protection,
you must connect a wire from the transmitter to ground as shown in
Figure 18 to make the protection effective. We recommend that you use
a size 8 AWG (American Wire Gage) or (8.37mm
2
) bare or green
covered wire.
Figure 18 Ground Connection for Lightning Protection.
Electronics
Housing
Connect to
Earth Ground
Continued on next page