INTELLIGENT SERIES GAS SENSORS (iSERIES)

iSO2 SERIES

iSO2 Series Gas Sensor Datasheet | sps.honeywell.com/ast |

3

TABLE 4. iSO2 PARAMETERS

iSO2 parameters

Default Values

Configurable Range

Notes

OEM code

(First level)

Password is

customisable.* (

NoLock

will be set by default in

case the OEM lock is

not required)

No more than 6 characters

(ASCII format)

ü

* OEM code will be set by Honeywell during sensor

manufacturing. Code to be provided by OEM

Partner code

(Second level)

–

No more than 6 characters

(ASCII format)

ü

Once this code has been set by user, it is not possible to

change it

User factor 0: 100

User factor 1: 90

UF 2-3: Reserved

UF 4-9: Customisable

–––––––––––

User factors can be

added to include auto-

compensation for using

different membranes or

instruments

10 allocated slots

–––––––––––

2 user factors are

already implemented (no

additional membrane

and with recommended

membrane), 2 are reserved

and the remaining 6 can be

customised

ü

*

ü

**

* User factor 0 and 1 programmed into the sensor during

manufacturing. Additional User Factors can be added to the

selectable list during the manufacturing process. This user

factor has to be provided by the user.

** Users can select the desired user factor from the selectable

list

Zero (clean air)

0 ppm

û

Calibration is performed at two points throughout the

operating range of the sensor. The calibration points are

defined by the zero and span values. The zero value represent

the response of the sensor in clean air

Span (target gas)

20 ppm

ü

Span is the calibration point that is done in the presence of

the target gas. The span concentration can be configured

through the communication protocol

Low

2 ppm

Limit LOW lower: 0.2

Limit LOW upper: 100

ü

High

10 ppm

Limit HIGH lower: 0.2

Limit HIGH upper: 100

ü

STEL

5 ppm over 15 minutes

Limit STEL lower: 0.2

Limit STEL upper: 100

ü

Short-Term Exposure Limit: STEL is a limit value above

which exposure to a chemical substance should not occur. It

usually references a 15-minute period. STEL works to prevent

adverse health effects along with other unwanted effects due

to peak exposure that could possibly not be controlled by the

application of an 8 hour TWA limit

TWA

2 ppm over 8 hours

Limit TWA lower: 0.2

Limit TWA upper: 1000

ü

Time-Weighted Average: TWA for chemical exposure can be

used when each of the chemical concentration and time for

exposure varies over time. It conveys the average exposure

to a contaminant to which workers may be exposed without

adverse effect over a period of time such as an 8-hour day or

40-hour week (an average work shift). The measurement is

expressed in units of ppm

The recalibration alarm will be triggered when either the countdown or the accuracy threshold are reached (whichever is triggered first).

Countdown timer

(Cal due days)

180 days

ü

The alarm will be flagged when the countdown reaches 0. The

countdown restarts when the sensor is calibrated

Accuracy

threshold

±20%

±10% to ±50%

ü

The predictive calibration estimation will depend on the

accuracy of the sensor (this parameter can be configured by

the user). The tighter the accuracy value, the more frequent

calibration needed. The sensor will request a recalibration when

the default accuracy (±20% of measuring value) is reached

The EoL alarm will be triggered when either the countdown or the future prediction algorithm conditions are met

Future prediction

algorithm

û

The algorithm triggers an alarm when the sensitivity < 50% of

original sensitivity at minimum recent temperature

Countdown timer

1825 days

û

The countdown timer is set for 1825 days, i.e. 5 years

Active by default

ü

ü

With the deadband enabled the sensor will read zero until the

concentration exceeds the deadband value. Is normally used

to prevent measurement oscillations. This function can be

configured to different limits

Incoming

1 ppm

Whole measurement range

ü

Incoming: As the reading decays down it will read zero once it

has fallen below the incoming threshold

Outgoing

1 ppm

Incoming < Outgoing

ü

Outgoing: As the reading increases it will read zero until it

exceeds the outgoing threshold

1 day

ü

A bump test is a brief exposure of the sensor to the target

gas. The test has the objective of verifying that the sensor

responds and the instrument acts accordingly. The sensor will

tell the user when the bump interval has been exceeded.