3
3-light Bulb-based Signals (e.g. older NJ International)
Wiring for 3-light bulb-based light signals is shown in Figure 2 using the Eastbound signal outputs; the connections are
similar for the Westbound signal outputs. You will need the current limiting resistors if the voltage rating of the bulbs is
lower than the input voltage to the
Block Animator/2
. For example, if the input voltage is 16V and the bulbs are rated at 12V
(get this information from the manufacturer of the signal) then we would suggest a resistor value of 100 ohms (e.g
www.mouser.com
part number 291-100-RC). If the input voltage is equal to or slightly lower than that of the bulbs then no
resistors are needed.
Current limiting resistors
(see text)
Bulb
Red
Bulb
Green
Bulb
Yellow
Figure 2 – 3-light bulb-based signal
2-light Bulb-based Signals (e.g. older NJ International)
Wiring for 2-light bulb-based light signals is shown in Figure 3 using the Eastbound signal outputs; the connections are
similar for the Westbound signal outputs. You will need the current limiting resistors if the voltage rating of the bulbs is
lower than the input voltage to the
Block Animator/2
. For example, if the input voltage is 16V and the bulbs are rated at 12V
(get this information from the manufacturer of the signal) then we would suggest a resistor value of 100 ohms (e.g
www.mouser.com
part number 291-100-RC). If the input voltage is equal to or slightly lower than that of the bulbs then no
resistors are needed.
Current limiting resistors
(see text)
Bulb
Red
Bulb
Green
Figure 3 – 2-light bulb-based signal
Position Light Signals (common anode LED or bulb-based)
Wiring for position light signals is shown in Figure 4 using the Eastbound signal outputs; the connections are similar for the
Westbound signal outputs. For common anode LED signals you MUST use current limiting resistors! You’ll also need
current limiting resistors with bulb-based signals if the voltage rating of the bulbs is lower than the input voltage to the
Block
Animator/2
. For example, if the input voltage is 16V and the bulbs are rated at 12V (get this information from the
manufacturer of the signal) then we would suggest a resistor value of 100 ohms (e.g
www.mouser.com
part number 291-100-
RC). If the input voltage is equal to or slightly lower than that of the bulbs then no resistors are needed. For LED signals the
value of the current limiting resistors depends upon the value of the input voltage to the
Block Animator/2
. For a 16V input
voltage we recommend a resistor value of either 390 ohms (e.g.
www.mouser.com
part number 293-390-RC) or 330 ohms
(e.g.
www.mouser.com
part number 293-330-RC); you should use ½ watt resistors. Use a higher value for the center LED;
we recommend a value of 680 ohms (e.g.
www.mouser.com
part number 291-680-RC).
