Pub. 42004-438M
300 Series Emergency Telephone Manual
Page 26 of 50
P:\Standard IOMs - Current Release\42004 Instr. Manuals\42004-438M.docx
04/19
Extreme Cold Temperature Option
RED ALERT
®
emergency telephones equipped with the extreme cold temperature option (-003 and -004
models) can operate to −40 °C (non-option models are rated to −20 °C). This option includes two
identifying features; a plug-in power supply and non-tactile push buttons.
Each telephone is shipped with a plug-in power supply that requires a 120 V ac input to provide a 5 V dc
output to the unit. The power supply is equipped with a 4-foot power cable with integral connector that
plugs into
P17
on the telephone PCBA. Jumper
P17
must be removed prior to plugging in the power
supply.
1.
Remove the jumper from
P17
pins 3 and 4.
2.
Plug the jumper into the adjacent
J18
header (see Figure 33 for the connector locations).
3.
Plug the power supply connector into header
P17
.
N
OTE
:
The external power supply provided with these models does not provide telephone line power for
communications. It simply activates a heater circuit to allow operation to −40 ºC.
The -003 and -004 models also have non-tactile (non-moveable) push buttons (
HELP
and/or
CALL
)
installed in place of the standard tactile (moveable) push buttons. Use of non-moveable switches
eliminates the possibility of water or melting snow from collecting and freezing behind the push button,
ultimately preventing the movement necessary for activation.
Figure 31. Extreme Cold Temperature
Piezo Button (Typical)
N
OTE
:
RED ALERT telephone models ending with the
FS
suffix are equipped with non-tactile
pushbutton(s) making them extreme cold weather capable. Operation to −40 °F (−40 °C) can be
accomplished by adding a No. 40404-045 Power Supply (120 V ac required).
