AirSense
Model 310en
Infrared Environmental CO
2
Sensor
Operator's manual
© Copyright 2011
AirSense Model 310en Operator’s Manual
3/9/15 Digital Control Systems Page: i
www.dcs-inc.net • 503/246-8110
Date
10/11/11
3/09/15
Ver01
AirSense Model 310en Operator’s Manual
Table of Contents
Preface......................................................................................... 1
Model Identification..............................................................1
Introduction................................................................................. 1
Displays and Indicators ............................................................... 2
Specifications .............................................................................. 3
Installation................................................................................... 4
Cover Removal .....................................................................4
Mounting...............................................................................4
Wiring...................................................................................5
Power Supply...................................................................5
Signal Output ...................................................................6
Cover Replacement...............................................................7
Field Adjustments........................................................................ 7
High CO2 Limit Adjustment.................................................7
High CO2 Limit Hysteresis Adjustment................................8
Analog Top-of-Scale Adjustment.........................................9
Altitude Correction Considerations .................................... 10
Altitude Correction Procedure .......................................10
Calibration................................................................................. 11
Verification Procedure........................................................11
Optional High Limit Contact Relay .......................................... 13
Setting High Limit Contact Polarity ...................................13
Disclaimers and Notices............................................................ 14
Operational Limitations......................................................14
Safety Critical Applications................................................14
Limited Warranty and Remedies............................................... 14
3/9/15 Digital Control Systems Page: ii
www.dcs-inc.net • 503/246-8110
AirSense Model 310en Operator’s Manual
Preface
This manual describes the Model 310en of the AirSense 310
Carbon Dioxide sensor family. The 310en, while similar in
external appearance and operation to previous 310e models,
has a slightly modified feature set and differences in the
location and operation of the user interface.
Model Identification
Because of its similarity to previous models, the Model
310en is most easily identified by the prefix “M310en” on
the unit’s serial number tag visible on the sensor circuit
board when the cover is removed.
All other AirSense 310e series sensors are covered in the
AirSense Model 310e Operator’s Manual.
Introduction
The AirSense Model 310en is a non-dispersive infrared
analyzer for measuring environmental CO2 concentration in
ventilation systems and indoor living spaces. Its default
measurement range of 0 - 2000 ppm (parts per million; 1000
ppm = 0.1%) covers the range required to monitor
compliance with ASHRAE or other ventilation efficiency
standards. For specialty applications the measurement range
can be easily increased up to 5000 ppm.
Packaged in a compact, distinctively styled enclosure, the
Model 310en can be discreetly installed anywhere from the
board room to the boiler room. Standard center wiring
access, fully floating outputs and power/signal mis-wiring
protection make installation a snap.
The Model 310en provides several output alternatives. A
voltage or 4 - 20 mA current output is standard. An optional
LCD readout is available. An optional relay contact can be
configured to open or close above a user-adjustable setpoint.
3/9/15 Digital Control Systems Page: 1
www.dcs-inc.net • 503/246-8110
AirSense Model 310en Operator’s Manual
Displays and Indicators
The Model 310en has a single green LED on the front panel
which illuminates whenever the unit is operating. This LED
is on steadily when the measured concentration is below the
high CO
2
limit, and blinks whenever the concentration is
above the limit.
The standard factory high CO
2
limit is 1000 ppm, but can be
adjusted in the field. The procedure for adjusting the high
CO
2
limit is described on page 7.
The display option adds a 4 digit liquid crystal display
(LCD) to the front panel. The display shows the measured
CO2 concentration in parts per million (ppm). 1000 parts
per million equals 0.1%.
3/9/15 Digital Control Systems Page: 2
www.dcs-inc.net • 503/246-8110
AirSense Model 310en Operator’s Manual
Specifications
Operating principle Non-dispersive infrared (NDIR)
Gas sampling method Diffusion or sample draw
Measurement range
400 - 2000 ppm CO
2
(standard)
Field adjustable to 5000 ppm
Typical drift (per year)
±75 ppm (@ 1200ppm)
Accuracy
±5% of reading or ±75 ppm,
Repeatability
±20 ppm
Recommended Calibration Interval Five Years
Response time Less than 1 minute
Operating temperature range
0 to 50 ° C
Operating humidity range 0 - 90% RH (non condensing)
Storage temperature
-30 to + 60 ° C
Power requirements 20 - 28 VRMS AC, 18 - 30 VDC
Power consumption Less than 2W @ 24 VAC
Calibration verification time 10 minutes typical
Dimensions 5.2" x 3.2" x 1.4"
Voltage output (linear) 0 - 10 volts DC
Current output (linear)
4 - 20 mA (R
L
≤ 500Ω)
Warm-up time 3 minutes
Weight 6.5 Oz. (.35 Kg)
Optional Digital Display 4 digit, .35" LCD
Optional setpoint range 0 to full scale
High
Limit
contact polarity jumper selectable
Contact contact rating 2A @ 24 VAC
Operating life expectancy 10 years typical
18 months, parts and labor through
repair or exchange
Warranty
3/9/15 Digital Control Systems Page: 3
www.dcs-inc.net • 503/246-8110
AirSense Model 310en Operator’s Manual
Installation
3.20"
1.60"
0.00"
2.10"
1.10"
0.00"
2.00"
2.75"
5.20"
3.50"
0.42"
Figure 1: AirSense Model 310en Mounting Dimensions
Cover Removal
To open the Model 310en use a coin in the slot on the
bottom to release the snap. Lift the cover up slightly to
disengage the closure and remove cover with a downward
motion to clear the catch at the top of the unit.
The locations of controls and terminals on the main circuit
board are shown in the Figure 2 on page 5.
Mounting
The Model 310en is designed for flush mounting with two
fasteners. The locations of the mounting points (shown in
Figure 1) allow direct mounting on a standard simplex
(single circuit) junction box. There is a wiring cutout in the
center of the unit near the terminal strips.
3/9/15 Digital Control Systems Page: 4
www.dcs-inc.net • 503/246-8110
AirSense Model 310en Operator’s Manual
Wiring
This section describes the external connections to the Model
310en. Figure 2 shows the location of the components
described in the following sections.
UP
button
User
Jumpers
Shorting block here
for current output.
Shorting block here
for voltage output.
Analog Output Selector
DOWN
button
Analog
Output
Upper Mountinhg
Screw Access
Wiring Access
+
-
C DCS 2010
32-0310-30
4-20mA
OUT
RLY
POWER
V
I
DN
-+
0-10V
UP
SEL
SW3
J4
SW1
SW2
JP4
JP1
JP3
JP5
JP2
Lower Mounting
Screw Access
Calibration Nipple
(Under sensor
electronics)
C
O2 SENSOR
Power In
20 - 28 VAC
18 - 30 VDC
(Polarity matters
for DC only)
Optional
Relay Contact
Output
Figure 2: Model 310en Component Locations
Power Supply
The Model 310en is not a loop powered device
The Model 310en will operate from an AC or DC input
voltage between the values called out in the specifications on
page 3. The power supply leads are connected to the twoterminal power connector. shown in Figure 2.
The Model 310en must never be connected directly to
line power. Operation at voltages higher than specified will
damage the unit and void the warranty.
When operating from DC power, the polarity of the power
leads must be as shown in Figure 2. Reversed polarity
3/9/15 Digital Control Systems Page: 5
www.dcs-inc.net • 503/246-8110
AirSense Model 310en Operator’s Manual
connection will not damage the unit, but will make it
inoperable until the connection is reversed.
Signal Output
The Model 310en provides either a 0 - 10 volt or a 4 - 20 mA
current loop output at the two terminals of the analog output
connector. The type of analog output is determined by the
setting of the analog output selector.
The unit is shipped from the factory with the top-of-scale set
to 2000 ppm. See the Analog Top-of-Scale Adjustment
section on page 9 to change the analog output range limits.
The analog output of the Model 310en is completely isolated
from the power supply. The common outputs of multiple
units can be connected together with no interaction
regardless of power supply hook-up.
Voltage
When the two bottom pins of the analog output selector are
connected with the shorting block, a voltage output appears
at the terminals marked ANALOG OUTPUT. The output
voltage increases linearly with CO
2
concentration from 0
volts at 0 ppm to 10 volts at the top-of-scale concentration.
Current
When the two top pins of the analog output selector are
connected with the shorting block, a current output appears
between the two terminals marked ANALOG OUTPUT.
The output current increases linearly from 4 mA at 0 ppm to
20 mA at the top-of-scale concentration. The unit is shipped
from the factory with the top-of-scale set to 2000 ppm. See
the Analog Top-of-Scale Adjustment section on page 9 to
change the top-of-scale value.
If the total resistance between the two terminals exceeds the
specified maximum loop resistance, the output current may
be erroneously low at high concentrations.
3/9/15 Digital Control Systems Page: 6
www.dcs-inc.net • 503/246-8110
AirSense Model 310en Operator’s Manual
Cover Replacement
Engage the top center of the cover under the latch at the top
of the base, then press the bottom of the cover onto the base
until it latches.
Field Adjustments
This section describes the features that can be field
configured and the procedures to make these changes. All
these procedures require the closing of one and sometimes
two jumpers.
When making adjustments to units without displays, the
current setting of the value being adjusted is reported by the
analog output. If there is no display, the procedures below
assume that the unit is set to voltage output and only a volt
meter is connected to the analog output terminal.
Note that the scaling of the analog output is not always the
same.
High CO
2
Limit Adjustment
An adjustable high CO
2
limit is a standard feature of the
Model 310en. The front panel LED changes from steady to
blinking when the indicated concentration is above the high
CO
2
limit value. An optional contact closure is available
which actuates when the high limit is exceeded.
The High CO
2
Limit value is adjusted as follows:
1. Note whether the shorting block at jumper JP5 is
covering both pins or only a single pin, then
borrow the shorting block and slide it over the two
pins of jumper JP3 (see Figure 2 on page 5).
2. If the display is present when JP3 is closed it will
show the current high limit setpoint in ppm CO
2
.
If there is no display the current value of the high
CO
2
limit is reported by the analog output scaled at
500 ppm/Volt. A high CO
2
limit of 1000 ppm is
indicated by and output voltage of 2.0 volts.
3/9/15 Digital Control Systems Page: 7
www.dcs-inc.net • 503/246-8110
AirSense Model 310en Operator’s Manual
3. The high CO
2
limit value is adjusted with the ‘UP’
and ‘DOWN’ buttons while JP3 is closed. When
JP3 is opened, the new relay setpoint takes effect
and is stored in non-volatile memory.
4. Remove the shorting block from JP3 to save the
value, and restore the shorting block to its original
position on JP5.
High CO
2
Limit Hysteresis Adjustment
The default high CO
2
limit hysteresis is approximately 40
ppm and can be inspected and adjusted between 0 and 200
ppm as follows:
1. Note whether the shorting block at jumper JP5 is
covering both pins or only a single pin, then
borrow the shorting block and slide it over the two
pins of jumper JP3 (see Figure 2 on page 5). Use a
narrow-bladed screwdriver or the like to
momentarily connect the two pins of JP1 while JP3
is closed.
2. If the display is present it will show the current high
CO
2
limit hysteresis value in ppm CO2.
If there is no display the current value of the high
CO
2
limit hysteresis is reported by the analog output
scaled at 20 ppm/Volt. A high CO
2
limit hysteresis
of 40 ppm is indicated by and output voltage of 2.0
volts.
3. The high CO
2
limit hysteresis value is adjusted with
the ‘UP’ and ‘DOWN’ buttons while JP3 is closed.
4. Remove the shorting block from JP3 and return it to
its previous position over one or both pins of jumper
JP5. When the jumper is opened, the new High
CO
2
Limit Hysteresis setpoint takes effect and is
stored in non-volatile memory.
3/9/15 Digital Control Systems Page: 8
www.dcs-inc.net • 503/246-8110
AirSense Model 310en Operator’s Manual
Analog Top-of-Scale Adjustment
This section refers to advanced features of the Model 310en.
2000 ppm full scale users need not perform this adjustment.
Unless explicitly ordered otherwise, the Model 310en ships
from the factory set for an analog output range of 0 to 2000
ppm.
The top-of-scale concentration (i.e. the concentration at
which the analog output is at its maximum value) can be
adjusted between 500 and 5000 ppm.
To change the top-of-scale value use the following
procedure:
1. Record whether the shorting block at jumper JP5
is covering both pins or only a single pin, then
borrow the shorting block and slide it over the two
pins of jumper JP4 (see Figure 2 on page 5).
2. If the display is present it will show the current topof-scale value in ppm.
If there is no display the current top-of-scale value is
indicated by the analog output at a scaling of 500
ppm/volt.
3. Use the ‘UP’ and ‘DOWN’ buttons to adjust the topof-scale to the desired value. A top-of-scale setting
of 5000 ppm corresponds to an output voltage of 10
volts.
4. Remove the shorting block from JP4 to save the
value, and restore the shorting block to its original
position on JP5.
3/9/15 Digital Control Systems Page: 9
www.dcs-inc.net • 503/246-8110
AirSense Model 310en Operator’s Manual
Altitude Correction Considerations
ALTITUDE
CORRECTION TABLE
The Model 310en is factorycalibrated for operation at sea
level. When operated at higher
elevations, the calibration will
correct for altitude as the unit
detects outside air concentration
Altitude
[feet]
Multiplication
Factor
0 1.0
500 1.02
In applications where the detected
CO
2
concentration does not
routinely fall close to outside-air
levels, the procedure below can be
used to set the operating elevation.
1000 1.03
1500 1.05
2000 1.07
2500 1.08
Beware that this procedure
works only on units that are
calibrated for sea level
operation.
3000 1.10
3500 1.12
4000 1.14
4500 1.16
Altitude Correction Procedure
To adjust the calibration of a unit
currently calibrated for sea level
operation to a new altitude proceed as follows:
5000 1.18
1. Let the Model 310en stabilize to the ambient CO2
concentration, and record the reading in ppm. If the
reading is greater than 1500 ppm, wait for a lower
reading before performing this procedure.
2. Multiply the reading by the scale factor corresponding to
the operating altitude in the altitude correction table.
For instance if the unit is operating at an altitude of 4000
ft, the scale factor from the table is 1.14. If the
concentration reads 420 ppm, multiply 420 times 1.14
giving 478 ppm. Adjust the display to read 480.
3. Remove the Model 310en’s cover (see cover removal
procedure on page 4).
4. Note whether the shorting block at jumper JP5 is
covering both pins or only a single pin, then borrow the
shorting block and slide it over the two pins of jumper
JP2 (see Figure 2 on page 5). Use the 'UP' and 'DOWN'
3/9/15 Digital Control Systems Page: 10
www.dcs-inc.net • 503/246-8110
AirSense Model 310en Operator’s Manual
buttons to change the indicated concentration to the value
just calculated.
If there is no display the indicated concentration is
reported by the analog output with a scaling of 200
ppm/volt.
5. Remove the shorting block from jumper JP2 and return it
to its previous position over one or both pins of jumper
JP5.
6. Replace the cover (see procedure on page 7).
Calibration
This section describes the calibration verification procedure
and calibration adjustment procedures.
Verification Procedure
A quick but approximate calibration verification can be done
by supplying the unit with outside air and letting the reading
stabilize. CO2 concentrations in outside air are typically
between 375 and 450 ppm.
A more accurate calibration check requires the use of
calibration gas of known concentration. 2000 ppm
calibration gas is recommended A calibration kit that
includes a digital display is available from the factory.
To verify the Model 310en's calibration, proceed as follows:
1. Remove the front cover of the unit (see procedure on
page 4).
2. If there is no display on the unit being calibrated, connect
a meter to the analog output terminals. Check the setting
of the analog output selector (see Figure 2 on page 5) to
determine whether the unit is set for voltage or current
output.
3. Locate the calibration nipple under the sensor’s circuit
board as shown in Figure 3.
3/9/15 Digital Control Systems Page: 11
www.dcs-inc.net • 503/246-8110
AirSense Model 310en Operator’s Manual
4. Remove the dust
cover from the
barbed calibration
nipple by grasping
its top with a pair of
needle-nose pliers
and pulling straight
back.
5. Attach a 1/8 “ ID
flexible tube to the
nipple and establish
a flow of between
50 and 100 cc/min
(0.002 to 0.004
SCFM) of 2000
ppm or or lower
concentration
calibration gas through the sensor. Allow approximately
two minutes for the reading to stabilize.
6. If the reading differs by less than ± 50 ppm from the
known concentration of the calibration gas, no adjustment
is recommended; proceed directly to step
9.
Figure 3: Showing location of
calibration nipple
Otherwise note whether the shorting block at jumper
JP5 is covering both pins or only a single pin, then
borrow the shorting block and slide it over both pins of
jumper JP2 (see Figure 2 on page 5).
7. Use the 'UP' and 'DOWN' buttons (see Figure 2 on page
5) to adjust the reading.
8. When the reading agrees with the concentration of the
calibration gas, remove the shorting block on jumper JP2,
and replace in its original position at jumper JP5.
9. Turn off the calibration gas flow, disconnect the gas
tubing from the calibration nipple and replace its dust
cover. Remove the meter leads from the terminal strip
and replace the front cover (see procedure on page 7).
3/9/15 Digital Control Systems Page: 12
www.dcs-inc.net • 503/246-8110
AirSense Model 310en Operator’s Manual
Optional High Limit Contact Relay
The high CO2 limit relay option provides a dry (i.e.
unpowered) contact closure that activates when the detected
concentration rises above the high CO
2
limit. The high limit
is adjustable from 0 to 5000 ppm.
Setting High Limit Contact Polarity
The polarity of the high limit contact is set with jumper JP5
as shown in the table below.
Jumper JP5 Relay Operation
CLOSED
(factory default)
normally open
closes above setpoint
normally closed
opens above setpoint
OPEN
To open jumper JP5 remove the shorting block from the two
pins, and replace it so that it engages only a single pin of the
jumper. The shorting block should not be discarded; it is
required for all field calibration procedures.
3/9/15 Digital Control Systems Page: 13
www.dcs-inc.net • 503/246-8110
AirSense Model 310en Operator’s Manual
Disclaimers and Notices
Operational Limitations
The standard Model 310en has the following operational
limitations:
1. The unit is not intended for routine operation at CO
2
concentrations below 400 ppm.
2. The unit expects to see outside-air CO
2
concentrations
for at least a few hours every few weeks.
For CO
2
sensing applications where these two limitations
can not be met, contact Digital Control Systems for guidance
on achieving maximum accuracy under these conditions.
Safety Critical Applications
DCS products are not designed, intended or authorized for
use in life safety systems or devices where failure of the
Model 310en to perform to specification may be reasonably
expected to result in significant risk of injury or death.
Limited Warranty and Remedies.
DCS warrants to Buyer of the AirSense Model 310en that
for 18 months from the date of shipment of Products to the
Buyer that Products will substantially conform with the
product specifications agreed to by DCS. This warranty is
not transferable.
This warranty does not cover:
Defects due to misuse, abuse, or improper or inadequate
care, service or repair of Products;
Defects due to modification of Products, or due to
alteration or repair by anyone other than DCS; or
Problems that arise from lack of compatibility between
DCS’ Products and other components used with those
Products or the design of the product into which
Products are incorporated. Buyer is solely responsible
for determining whether Products are appropriate for
Buyer's purpose, and for ensuring that any product into
3/9/15 Digital Control Systems Page: 14
www.dcs-inc.net • 503/246-8110
AirSense Model 310en Operator’s Manual
which Products are incorporated, other components used
with DCS’ Products, and the purposes for which DCS’
Products are used are appropriate and compatible with
those Products.
The warranty in this section is in lieu of all other
warranties, express or implied. DCS expressly disclaims
all implied warranties, including the warranties of
merchantability and fitness for a particular purpose.
DCS is not responsible in any way for damage to a
product, property damage or physical injury resulting in
whole or in part from (1) improper or careless use, (2)
unauthorized modifications, or (3) other causes beyond
DCS’ control. In no event is DCS liable to the buyer or
any other person for cost of procurement of substitute
goods, loss of profits, or for any other special, incidental
or consequential damages.
To obtain service under this warranty, unless DCS agrees
otherwise, Buyer must obtain a returned material
authorization (RMA) number from the factory, pack any
nonconforming Product carefully, and ship it, postpaid or
freight prepaid, to the address provided when the RMA
number is issued. Buyer must include a brief description of
the nonconformity. Any actions for breach of this warranty
must be brought within six months of the expiration of this
warranty.
If DCS determines that a returned Product does not conform
to the warranty in this section, it will either repair or replace
that Product, at DCS’ discretion, and will ship the Product
back to Buyer free of charge. At DCS’ option, DCS may
choose to refund to Buyer the purchase price for a
nonconforming Product instead of repairing or replacing it.
Units returned for service under this warranty and
determined on examination to be operating properly are
subject to a service charge.
3/9/15 Digital Control Systems Page: 15
www.dcs-inc.net • 503/246-8110
Loading...