Sierra Monitor Corporation 2400-01 User manual

Sierra Monitor Corporation
1991 Tarob Court, Milpitas, CA 95035
[phone]
[phone]
VAULT GAS MONITOR
Model 2400-01
Model 2400-21
SMOKE DETECTOR OPTION
MODEL 2404-00
APPLICABILITY & EFFECTIVITY
This manual provides instructions for the following Sierra Monitor products:
Model
Description
2400-01 Vault Gas Monitor
2400-21 Vault Gas Monitor, Low CO
2404-00 Smoke Detector for 2400
The instructions are effective for the above models as of October 1, 1996
Instruction Manual Part Number: T10007
Rev. B1

Instruction Manual
Table of Contents
TABLE OF CONTENTS
SECTION PAGE
1. PRODUCT DESCRIPTION 1
1.1 Introduction 1
1.2 General Description 1
1.2.1. Mechanical 1
1.2.2. Uninterrupted Power Supply 1
1.2.3. Alarm Relays 2
1.2.4. Alarm Indicators 2
1.2.5. Test Switches 2
2. INSTALLATION 3
2.1 Unpacking and Inspection 3
2.2 Installation & Set-Up 3
2.2.1. Enclosure Mounting 3
2.2.2. External Connections 3
2.2.3. Start-Up 3
3. OPERATION 4
3.1 Status Indication 4
3.2 Function Tests 4
4. CALIBRATION 5
4.1 Frequency of Calibration 5
4.2 Calibration Procedure 5
4.3 Maintenance 5
5. INFORMATION TO INSTALLERS 6
5.1 Discussion & Background 6
5.2 Electrical Adjustments 6
6. SMOKE DETECTOR 8
6.1 Product Description 8
6.2 Installation 8
6.3 Operation 8
7. NICKEL CADMIUM BATERIES 9
7.1 Nickel Cadmium Battery Operation 9
8. SPECIFICATIONS 10
9. PART NUMBERS & SPARE PARTS LIST 11
APPENDIX: Figures 1 thru 6

Instruction Manual
Page: 1 Model 2400 Vault Gas Monitor 2/03
1.1 INTRODUCTION
The Model 2400 series Vault Gas Monitors
provide continuous monitoring of Methane
(and other Combustibles) and Carbon
Monoxide gas simultaneously in a confined
space to provide safety for personnel and to
reduce the hazard of gas explosion. Two
versions of the Model 2400 are available.
The 2400-01 has a Carbon Monoxide
sensor with a range of 50-200 ppm CO.
The Low CO version, 2400-21, has a range
of 0-100 ppm CO for current OSHA and
NIOSH regulations with the Model 2400.
Features of the Model 2400 series products
include:
- Local visual and audible alarms.
- Remote Visual Alarm Indication Box
(Model 2401 option)
- Ambient temperature change
compensation.
- Long-life solid state gas and
temperature sensors.
- Battery back-up for uninterrupted
power supply.
- Continuous battery voltage monitoring.
- RFI/EMI AC Power Line Filter
together with electrical and mechanical
design to reduce electro-magnetic
interference.
- Five alarm relay contacts.
- User selectable active or passive relay
alarm test.
- Single PC board assembly and modular
harness construction for easy
maintenance.
- Alarm Test button
- Mil Spec Amphenol connectors for AC
and alarm lines.
- Smoke Detector (Model 2404-00
option) with battery back-up.
- Fused Battery Charging Circuit.
- Fused Vent Relay (K3).
1.2 GENERAL DESCRIPTION
1.2.1. MECHANICAL
The Model 2400 is housed in a NEMA
3 type hinged enclosure with the input
power connector, relay output
connector and sensors accessible on
the sides and bottom.
SENSORS:
Three sensors are mounted on the
bottom of the enclosure. This
orientation provides protection
from dust and moisture
contamination. The sensors can
easily be replaced without removal
of the monitor from its permanent
mounting. Two of these sensors
are for gas detection and the third
contains two separate
thermocouple devices to permit
direct measurement of ambient
temperature. The Combustible and
Carbon Monoxide sensors are
metal-oxide semiconductor type
solid state devices for long life.
The electrical resistance of the
sensors is inversely proportional
to the gas concentration.
CARBON MONOXIDE: This
sensor is specifically designed to
detect carbon monoxide gas. The
2400-01 has a metal-oxide
semiconductor type solid state
sensor for long life with a
calibration range between 50 ppm
and 200 ppm. The 2400-21 has an
electrochemical type sensor with a
calibration range between 10 ppm
and 100 ppm. The sensors are
relatively insensitive to methane.
METHANE: This metal oxide
semiconductor type solid state
sensor is designed to detect
methane gas and other explosive
gases. The calibration range is
between 5% and 25% of LEL for
methane. The sensor is relatively
insensitive to CO.
TEMPERATURE: Each
semiconductor type sensor is
compensated for variations of
ambient temperature over a range
of 0 to 40oC.
CONNECTORS:
Mil-Spec Amphenol connectors
are used for the relay and remote
indicator outputs and for the
power input to provide
compatibility with vault hardware
specifications.
1.2.2. UNINTERRUPTED POWER
SUPPLY (UPS)
The AC/DC power supply is factory
configured for 120 VAC (60 Hz)
operation. An EMI/RFI Line Filter is
provided to filter the AC power line
from high frequency noise. The power
1. PRODUCT DESCRIPTION 1. PRODUCT DESCRIPTION

Instruction Manual
Page: 2 Model 2400 Vault Gas Monitor 2/03
supply includes a built-in constant
current Ni-Cad battery charger with up
to one ampere capacity. Batteries can
be fully charged in 14 hours. The six
"D" size NiCad pack batteries will
provide up to nine hours back-up. A 5
volt 0.5 Amp regulator supplies power
to the analog and digital sections. The
battery voltage is constantly monitored
and if it fails, a low battery voltage
signal is generated. The UPS and DC
electronics are electronically protected
against short circuits.
1.2.3. ALARM RELAYS
There are five alarm relays. All are
single-pole double-throw with 6 amp
dry non-inductive contacts at 120/240
volts AC.
FAILURE RELAY: The failure relay
is activated when either gas sensor
becomes defective (open sensor
resistance or no heater voltage). The
failure relay is also activated if both
the AC and battery back-up power
supplies fail.
CARBON MONOXIDE RELAY:
The Carbon Monoxide Relay is
activated when the concentration
exceeds the calibrated threshold setting
(100 ppm CO on the 2400-01 and 25
ppm CO on the 2400-21).
COMBUSTIBLE RELAY: The
Methane Relay is activated when the
concentration of Methane exceeds the
calibrated threshold setting (5000 ppm
CH4).
VENTILATION RELAY: The
Ventilation Relay is activated when
either the CO or CH4gas
concentration exceed their calibration
levels. The common contact of the
ventilation relay is fused with a 4 amp
socketed micro-fuse.
REMOTE INDICATOR RELAY:
The Remote Indicator Relay is
activated when either the Failure Relay
or the Ventilation Relay is activated.
Any of the following conditions will
activate the Remote Indicator Relay
which is normally connected to the
Remote Indicator box:
* Excess Carbon Monoxide
* Excess Methane
* AC and Battery Failure
* Carbon Monoxide sensor
failure
* Methane sensor failure.
1.2.4. ALARM INDICATORS
The front panel has one audible alarm,
eight annunciator lights and one test
button.
AUDIBLE ALARM: The Audible
Alarm will sound when either the CO
or CH4gas concentration exceeds the
respective calibrated threshold levels.
The Audible Alarm produces a
continuous tone of 2900 Hz at 68 dB.
POWER FAILURE ALARM: The
Power Failure Alarm consists of two
lamps; a Power-On Lamp (green) and
a Low Battery Indicator (red). The
Power-On indicates that the +5 VDC
and 8.2 VDC supplies are present. The
Low Battery indicator is activated
when the battery voltage drops below
+6.2 VDC.
CARBON MONOXIDE STATUS
LIGHTS: The three CO status lights
are: Safe (green), Alarm (red) and
Sensor Failure (red).
COMBUSTIBLE STATUS
LIGHTS: The three Combustible
status lights are: Safe (green), Alarm
(red) and Sensor Failure (red).
1.2.5. TEST SWITCHES
Two test switches are provided to
allow functional testing of the monitor
outputs:
GENERAL TEST: A momentary
push button is provided on the front
panel for testing the operation of all
lamps, three relays (Ventilation,
Combustible gas, and Carbon
Monoxide gas) and the Audible Alarm.
A slide switch is located on the
electronics board to enable or disable
the relay portion of this test. In the up
position (ON), the test will be active.
In the down position (OFF), the test
will be passive. (This switch (SW1) is
located on the left hand side of the
circuit board.
FAILED SENSOR TEST: An
auxiliary momentary push button test
switch (SW3), located in the bottom
right hand corner of the circuit board,
is provided for testing the Failure and
Remote Indication relays and the
Sensor Failure lamps by simulating a
sensor failure.

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Page: 3 Model 2400 Vault Gas Monitor 2/03
2.1 UNPACKING AND INSPECTION
Remove the instrument from its packing
container and inspect to insure that all
items listed on the packing slip have been
received in good condition.
Open the door by loosening the two screw
clamps. Inspect the internal electronics and
wire harnessing to insure that no damage
has occurred during shipment. The battery
pack connector located above the door
hinge is shipped disconnected and should
be left open until the monitor is ready to be
turned on.
2.2 INSTALLATION AND SET-UP
2.2.1. ENCLOSURE MOUNTING
Mount the enclosure in the selected
location by bolting the top and bottom
flanges to a vertical surface.
2.2.2. EXTERNAL CONNECTIONS
A.C. POWER PLUG: Connect the
three pin amphenol plug to the main
(user supplied) AC power cord. Refer
to Figure 1 for pin configuration.
ALARM RELAY PLUG: Connect
the 24 pin amphenol connector plug to
the required (user supplied) signal,
light or fan activation lines. Refer to
Figure 1 for pin configuration.
2.2.3. START-UP
POWER ON: Connect the three pin
power plug to the receptacle on the
upper left side of the enclosure. After
a short pause the audible alarm will
sound (on the Model 2400- c21, only
the combustible alarm will sound), the
alarm lights will light on the front
panel and the calibration lights inside
the enclosure will light. The alarms
will stabilize within five minutes at
which time the audible will cease and
the "safe" lights on the front panel will
light.
CONNECT BATTERY PACK:
Connect the mating parts of the battery
pack connector to enable the battery
back-up and begin the continuous
charging of the batteries. (Initial
charge may be low).
MONITOR STABILIZATION: To
avoid false alarms during the sensor
stabilization period and to fully charge
the battery pack, allow twenty four
hours before connecting the alarm
outputs.
ALARM CONNECTION: Connect
the twenty four pin connector to the
receptacle on the lower left side of the
enclosure.
2. INSTALLATION

Instruction Manual
Page: 4 Model 2400 Vault Gas Monitor 2/03
The Model 2400 requires no operator
intervention except for periodic calibration.
The following information can be followed
to insure that the initial installation is
correct and to insure that the external
wiring is correct.
3.1 STATUS INDICATION
Table 1 describes status of each indicator
under various conditions:
3.2 FUNCTION TESTS
The following function tests can be
performed to confirm the conditions
described in Table 1.
TEST LIGHTS: Press the "Test Lights"
button and check that all panel lights turn
"ON" and that
the audible alarm turns on. If the "active "
relay test is used the carbon monoxide,
combustible and vent relays will activate
during this test.
FUNCTION TEST: Apply gas from a
cigarette lighter (WITHOUT FLAME) or
other high concentration source to the CH4
sensor and check that the Combustible
Alarm light goes on.
BATTERY BACK-UP TEST:
Disconnect main AC and check that
monitor still functions to confirm that the
batteries are charged and functional.
SENSOR FAILURE TEST: Open door
of enclosure and remove either sensor
connector from the receptacle on the board
and check front panel for a sensor failure
alarm. (NOTE: To remove the sensor
connector grip the connector housing with
pliers - do not pull the wires)
3. OPERATION INSTRUCTIONS
CONDITION LIGHTS RELAYS AUDIBLE
SYSTEM CO METHANE
POWER BATT SAFE ALM. FAIL SAFE ALM. FAIL CO CH4 FAIL VENT REMOTE
AC ON
SAFE ON ON ON
CO ALARM ON ON ON ON ON ON ON
CH4 ALARM ON ON ON ON ON ON ON
CO FAIL ON ON ON ON ON
CH4 FAIL ON ON ON ON ON
LOW BATT ON ON ON ON ON ON
AC OFF
BATT OK ON <--------------- SAME AS ABOVE ------------------------->
BATT LOW <---------------- SAME AS ABOVE ------------------------> ON ON
BATT DEAD
TEST LIGHTS
ACTIVE ON ON ON ON ON ON ON ON ON ON ON ON
PASSIVE ON ON ON ON ON ON ON ON ON
TABLE 1
STATUS INDICATORS

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Page: 5 Model 2400 Vault Gas Monitor 2/03
4.1 FREQUENCY OF CALIBRATION
The manufacturer recommends that the
Model 2400 be calibrated every 180 days.
4.2 PROCEDURE
PREPARATION: Open the door of the
enclosure and locate the two adjusting
potentiometers which are immediately
above the connectors for the two gas
sensors. Adjustment of these
potentiometers raises and lowers the
sensitivity of the respective gas sensor.
Also locate the two LED indicators near the
respective potentiometers. The LED on the
left is the carbon monoxide calibration
indicator, the LED on the right is the
combustible calibration indicator.
CALIBRATION - METHANE: Apply
5000 ppm methane calibration gas at 50
cc/minute to the combustible sensor and
watch for the calibration indicator to turn
on. If the indicator turns on within five
seconds of application of the gas and turns
off within five seconds of removal of the
gas the sensor is correctly calibrated. If the
indicator fails to turn on keep the gas on
the sensor and adjust the potentiometer
clockwise until the calibration indicator
turns on. If the indicator turns on too
quickly and stays on for too long after
removal of the gas adjust the potentiometer
counter-clockwise to decrease the
sensitivity and repeat the calibration
process.
CALIBRATION - CARBON
MONOXIDE: Apply carbon monoxide
calibration gas to the CO sensor.
Calibration gas for the 2400-01 is 100 ppm
CO at 50 cc/minute and for the 2400-21 use
25 ppm CO (factory standard), or 35 ppm
at 100 cc/minute. Watch for the calibration
indicator to turn on. If the indicator turns
on within one minute of application of the
calibration gas (within two minutes for the
2400-21) and turns off within one minute
after removal of the calibration gas (within
two minutes for the 2400-21) the sensor is
correctly calibrated. Adjust the sensitivity
as described in the preceeding paragraph.
NOTE: Sierra Monitor Corporation
recommends using the Model 26 Gas
Sensor Calibrator, Model 1200-26.
4.3 MAINTENANCE
Except for periodic calibration as described
above, no routine maintenance is required.
The following items may require
replacement due to age and deterioration:
SENSOR: Unplug the failed sensor by
grasping the top of the white plastic
connector housing (use pliers). (Do not
grasp the bottom of the housing which is
permanently attached to the circuit board.)
Pull firmly to unplug the sensor. Remove
the large nut which holds the sensor in the
enclosure frame. Discard the old sensor
and replace by reversing these directions.
With the semiconductor sensors allow the
new sensor to stabilize for at least one day
and re-calibrate. The electrochemical
sensor on the 2400-21 will stabilize in less
than one hour.
BATTERY PACK: Disconnect the
battery harness at the in-line connector on
the battery pack. Cut two large "ty-wraps"
and lift out the battery pack. Install the
new battery pack. Use new "ty-wraps to
secure the pack. Plug in the connector.
4. CALIBRATION INSTRUCTIONS

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5.1 DISCUSSION & BACKGROUND
Field data shows that the Vault Gas
Monitor operates extremely well in the
installed vault. This is because the
environmental conditions and the monitor
are stable.
Various minor difficulties occur during the
installation and initial check-out due to
major variations in climatic conditions and
due to the inspection occurring very
quickly after the monitor has been turned
on.
Upon initial turn-on the monitor requires a
stabilization period which varies based on
the amount of time it has been stored and
the temperature during stabilization.
Longer storage times and colder
temperatures increase the stabilization time.
As the specified lower operating
temperature of the monitor is 32 degrees
(F) it may not be possible to perform
function checks in assembly areas where
the temperature is below freezing.
5.2 ELECTRICAL ADJUSTMENTS
The electrical adjustments described below
are temporary adjustments to be used only
during installation or for temporary
adjustment until calibration is performed.
For ongoing operation the more accurate
calibration method described in this manual
should be followed.
1. Connect the common side of a DC
voltmeter to the ground loop marked
"GT1" on the upper side of the PC
board assembly.
2. Use the other meter lead to read the
"reference voltage" for the CO channel
by touching (test point) TP4 which is
one inch from the bottom of the board
and slightly left of center. The
reference voltage should be
approximately 2.5 volts, + 0.2 volts,
for the 2400-01 or approximately 1.5
volts, + 0.2 volts, for the 2400-21 and
varies lower in cold temperature or
higher in warm temperature.
3. Read the voltage on TP3 located to the
left of TP4 and slightly lower. This
voltage is "0" during a failed sensor
alarm and is greater than 2.5 volts
(2400-01) or greater than 1.5 volts
(2400-21) during a CO alarm. The
correct set-point for a safe condition is
1.5 volts for the 2400-01 and 1.0 volts
for the 2400-21 (25 ppm alarm).
Adjust the voltage using the
potentiometer R35 at the lower left
corner of the board.
4. Adjustment of the combustible sensor
is approximately the same.
4.1. Read the voltage at TP5 (one
inch from the bottom of the
board and slightly right of
center) to confirm that the
reference is approximately 2.5
volts.
4.2. Set the voltage at TP6 (right
side of board and lower than
TP5) at 1.0 volt by adjusting
R52 at the lower right corner
of the board.
4.3. For Model 2400-01, a rough
functional test can be made by
applying butane from a
cigarette lighter to each sensor
(note that the center of the
three sensors is the
temperature probe and the
outer two are the gas sensors).
When a small amount of gas is
applied to the right sensor the
combustible alarm should go
on within one or two seconds.
When gas is applied to the left
hand sensor the CO alarm
should go on in 15 seconds or
less.
5. To understand the adjustment
of the unit the installer can
follow this exercise:
5.1 Read and note the reference
voltage TP5.
5.2 Attach the meter to TP6 to
read the sensor voltage on the
combustible sensor. Note that
while this voltage is above "0"
and below the TP5 value the
unit indicates "safe" condition
for combustible. Record the
TP6 voltage for use in step 5.8
below.
5.3 Adjust the potentiometer R52
so that the TP6 reading drops
to "0". Note that the monitor
is now in "sensor fail".
5.4 Adjust R52 so that the TP6
reading is in the safe range and
apply cigarette lighter gas.
Note that the TP6 voltage
5. INFORMATION TO INSTALLERS

Instruction Manual
Page: 7 Model 2400 Vault Gas Monitor 2/03
increase above the TP5 value
and the gas alarm occurs.
5.5 If 5000 ppm methane gas is
available perform step 4 test
using the calibration. Note
that the change in voltage is
much less dramatic.
5.6 It should now be clear that
TP6 should be adjusted above
"0" to avoid false "sensor fail"
alarms and sufficiently below
TP5 so that the change due to
calibration gas causes TP6 to
go higher than TP5 and sets
off the alarm.
5.7 It is not necessary to repeat the
exercise on the CO side of the
system but the same actions
occur. Usually the voltage at
TP3 is adjusted closer to the
reference voltage than TP6
because the CO sensitivity is
100 ppm for the 2400-01
(compared to 5000 ppm
methane). For the Model
2400-21 the CO sensitivity is
25 ppm.
5.8 Return the TP6 voltage to the
level recorded in step 5.2
above or re-calibrate using the
correct concentration of gas.

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6.1 PRODUCT DESCRIPTION
The Model 2404 (Figure 3) is a
photoelectric, single station Smoke
Detector which is designed to be operated
in conjunction with the Sierra Monitor
Model 2400 Vault Gas Monitor. The
Smoke Detector contains the detection
electronics, an audible alarm, D.C. power
supply and dry contact relay connections.
Power to operate the Model 2404 is
provided by the regulated DC power supply
installed in the Model 2400. This supply is
backed up by the Model 2400 battery pack.
Prewiring of the internal connector in the
Model 2400 provides dry contact relay
output from the Gas Monitor to indicate
loss of power to the smoke detector or a
smoke alarm.
6.2 INSTALLATION
MOUNTING: The Model 2404 mounts to
a standard single gang or 4" octagonal
electrical box. To access the terminal block
on the electronics board use a small
jewelers screwdriver to depress the cover
release tab and open the hinged cover.
System wiring fits through the opening in
the back of the smoke detector.
WIRING: Install wires from the large
connector on the gas monitor to the
terminal strip in the smoke detector as
follows (see Figure 6):
6.3 OPERATION
The Smoke Detector is designed to operate
continuously. Monthly, the hinged cover
should be opened and the screen around the
optical unit should be cleaned with
compressed air or a vacuum. Do not use
cleaning solvents. If necessary, water on a
cotton swab may be used for cleaning. The
red LED on the cover flashes periodically
during normal operation.
The Smoke Detector may be tested using
the following procedure:
1. Hold a magnet, such as the end of a
magnetic screw starter immediately
against the center of the flat indent of
the case behind the cover hinge.
2. Keep the magnet in place for a
couple of seconds until the self-
diagnostic routine begins.
3. The self diagnostic routine starts
with a series of 4 to 7 LED blinks
followed by activation of the alarm
relay for five seconds. If the LED
blinks more than 7 times the detector
is too sensitive, if there are less than
4 blinks the detector is not sensitive
enough.
4. If the LED blinks indicate a problem,
open the cover and dust the internal
components using clean compressed
air. If the test still fails, replace the
smoke detector.
FUNCTION SMOKE DETECTOR GAS MONITOR
DC Positive Terminal # 1 Connector #N
DC Common Terminal # 2 Connector #P
Alarm Relay (common) Terminal # 3 Connector #Q
Alarm Relay (n/open) Terminal # 4 Connector #R
Figure 6: Wiring Connections - Smoke Detector
6. SMOKE DETECTOR

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7.1 NICKEL CADMIUM BATTERY
OPERATION
Nickel cadmium batteries such as those
used in the Model 2400 Vault Gas
Monitor are intended for use in
applications where the power demand will
be constant over a long (hours) period of
time (as opposed to a vehicle battery
which is designed for surge demand).
The Model 2400 battery pack is charged
with a very slow trickle charge which
would take 14 hours from depleted to
fully charged. Once the charge is
complete the current stops but the charger
voltage remains applied to insure full
charge at all times. If the batteries are
stored in this condition and are seldom
used they can be expected to have a
lifetime of three to five years. The failure
mechanism would be a very gradual loss
of capacity so that they may reach a point
where only a few minutes of back-up is
available compared to the nine hours
expected from new battery packs.
The loss of "memory" is accelerated when
the batteries are used frequently for short
durations (minutes) and then recharged.
When this use occurs the battery begins to
develop a memory which is equal to the
usage time experienced.
As it is expected that CEVs would have
reliable AC power the monitor is unlikely
to need to operate on the batteries very
frequently, and infrequent short demands
should not be enough to cause the
memory loss described above.
The best maintenance objective is to:
- Preserve the batteries with maximum
charge for as many years as possible.
- Be able to determine when batteries
are nearing the end of their useful life
so that replacement can be a
preventative action.
To accomplish both these objectives the
batteries should be "deep discharged"
approximately once every six months and
the length of the run time should be
measured. If the run time is less than the
expected length of a power failure the
battery pack should be replaced.
Test Points (identified as TP7 and TP8)
are provided on the lower left hand side of
the electronics board to allow
measurement of the charging current to
the batteries. This is a voltage
measurement across a .1 ohm resistor.
The charging (or discharging) current can
be calculated in amperes by multiplying
the voltage across TP7 and TP8 by ten.
7. NICKEL CADMIUM BATTERIES

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8. SPECIFICATIONS
GAS MONITOR
INPUT POWER 120 volts 60 Hz (240V option avail)
12 Watts Max
OPERATING TEMPERATURE
Standard 32 to 104oF (0 - 40oC)
Extended Temperature Option -4 to 140oF (-20 - 60oC)
CALIBRATION RANGE Carbon Monoxide: 50 - 200 ppm (2400-01)
Carbon Monoxide: 0 - 100 ppm (2400-21)
Methane: 2,500 - 12,500 ppm (5% - 25% LEL)
FACTORY CALIBRATION Carbon Monoxide: 100 ppm (2400-01)
Carbon Monoxide: 25 ppm (2400-21)
Methane 5000 ppm
RESPONSE TIME Less than 30 Seconds
ENCLOSURE NEMA 3-Type hinged front panel
INPUT CONNECTOR 3 Pin (AMPHENOL) Mil-Spec Type MS 3106A-14S-7s
OUTPUT CONNECTOR 24 Pin (AMPHENOL) Mil-Spec Type MS 3106A-2428S
BATTERIES Six "D" Size NiCad - 4 Ampere hour
OUTPUT RELAYS Five SPDT (FORM C)
6 AMP Non-Inducting @120/240VAC
6 AMP Non-Inducting @28VDC
1/8 HP Load
GAS SENSORS
2400-01 Two solid-state metal-oxide semiconductor sensors
in separate housings
2400-21 One solid-state metal-oxide semiconductor sensor
(Methane)
and one electrochemical sensor (CO) in separate housings
TEMPERATURE SENSOR Two solid state sensors
AUDIBLE ALARM 68db AT 2900 Hz
FUSE 1/4 AMP 250 VAC
SIZE 8 X 8 X 4 Inches (HWD) (20 X 20 X 10 cm)
WEIGHT 12 lb (5.5 Kg)
SMOKE DETECTOR
DETECTION PRINCIPLE Photoelectric
NOMINAL SENSITIVITY 3.3%/FT.
DIMENSIONS Diameter: 6.125", Height 2"
WEIGHT 1 pound
INDICATORS Red LED for power "ON"
Audible warning for alarm (85 dB)
RELAYS One SPST dry contact (2 amp @ 30VDC)
POWER 6.0 - 8.0 VDC

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9. PART NUMBERS & SPARE PARTS LIST
CALIBRATION ACCESSORIES
Model No. Description
1200-26 Gas Sensor Calibrator W/2 gas cylinders
1290-03 Gas Cylinder - Methane 5000 ppm
1290-05 Gas Cylinder - Carbon Monoxide 100 ppm
1290-08 Gas Cylinder - Carbon Monoxide 25 ppm
MODEL 2400 SERIES ASSEMBLIES
Model No. Description
2400-01 Vault Gas Monitor
(Modified for Smoke Detector Option)
2400-21 Vault Gas Monitor, LO CO
2401-00 Light Box for Entry Door (remote indicator
2402-00 Connector Kit (Connector hardware only)
2403-01 Connector Assembly (Includes hardware and wiring)
2404-00 Smoke Detector
MODEL 2400 SERIES SPARE PARTS
Part No. Description
SPJ21507 Assy: Combustible Sensor
SPJ21510 Assy: Carbon Monoxide Sensor, 50 - 200 ppm
SPJ21511 Assy: Thermistor Set
SPJ21514 Assy: Carbon Monoxide Sensor, 0 - 100 ppm
SPJ22021 Assy: Control Board
SPJ22023-1 Assy: Internal Control Harness
SPJ39039 Battery Bracket
SPJ44003 LED, red, MV5752
SPJ44009 LED, green (front panel)
SPJ44010 LED, red (front panel)
SPJ49005 Alarm, Sonalert SNP2
SPJ49028 Fuse, 1/2 amp
SPJ49071 Line filter, RFI
SPJ49073 Switch, CH8411K11 SPDT (SW1)
SPJ49076 Lense, red, for remote alarm box
SPJ49077 Lense, green, for remote alarm box
SPJ49078 Bulb, Sylvania 120PSB for remote alarm box
SPJ49085 Fuse, 4 Amp (Vent Relay -K3)
SPJ49088 Fuse, 2 Amp (Battery Charging Circuit)
SPJ62001 Washer, for Sonalert alarm
SPJ69025 Fuseholder
SPJ22003 Battery Pack + Ty-Wraps

Instruction Manual
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Instruction Manual
Page: 13 Model 2400 Vault Gas Monitor 2/03
VAULT GAS MONITOR
MODEL 2400
FAILURE
SENSOR
ALARM
FAILURE SENSOR
ALARM
SAFE
BATTERY
LOW
LIGHTS
TEST
ON
POWERSAFE
COMBUSTIBLE
MONOXIDE
CARBON
RELAY
CONNECTION
1/2AMP
FUSE
A.C. INPUT
.312 DIA. (4X)
MOUNTING HOLE
REPLACEABLE
CARBON MONIXIDE
(LOW ppm)
SENSORASSEMBLY
THERMISTOR
ASSEMBLY
REPLACEABLE COMBUSTIBLE SENSOR ASSEMBLY
LED (8X)
8.25
(21.0 cm)
4.25
(10.8cm)
8.75
(22.2 cm)
MATING
CONNECTOR
IS AMPHENOL P/N
97-3106A-14S-75
MATING
CONNECTOR
IS AMPHENOL P/N
97-3106A-24-285
MODEL 2400
VAULT MONITOR
OUTLINE & MOUNTING DIMENSIONS

Instruction Manual
Page: 14 Model 2400 Vault Gas Monitor 2/03
1.85"
6.1"
TEST SWITCH TO ACTIVATE SENSITIVITY LEVEL TEST MODE, HOLD MAGNET ON HINGE SIDE OF DETECTOR FOR MORE THAN 1 SECOND
MOUNTING
ALL BOXES
COVER RELEASE
SEE DETAILA
DETAILA
SIDE VIEW TERMINAL BLOCK
SINGLE GANG 4" OCTAGON MOUNTING
4" SQUARE OR WIREMOLD MOUNTING (No. 5739)
Sierra monitor corporation
Milpitas, C A 95035
MODEL 2404-00
SMOKE DETECTOR
BOTTOM VIEW
TO OPEN - PRESS SCREWDRIVER BLADE HERE
K2404A.CDR 10/3/95 MN 11
B1
MODEL 2404
SMOKE DETECTOR
FIGURE 3
SCALE: DATE: SHEET OF
DWG NO.
REV.FILE NO:
N/O (BY CUSTOMER)4COM (BY CUSTOMER)3 BLUE +5V (BY CUSTOMER)1GND (BY CUSTOMER)2BLACK YELLOW

Instruction Manual
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Instruction Manual
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Instruction Manual
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