Toxalert Tox-Refrig-ANA User Manual

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TOXALERT

REFRIGERANT SENSOR MODEL TOX-REFRIG/ANA

REFRIGERANTS MONITORED

R-11 R-22 R-123 R-141b R-500
R-12 R-113 R-134a R-152a R-502

*Many Others*

GENERAL DESCRIPTION:

Toxalert’s refrigerant sensor/transmitter is designed for
use in conjunction with Toxalert and other standard 4 to
20 mA loop or voltage controllers.
The Tox-Refrig/ANA refrigerant sensor is a metal oxide
semi-conductor (solid state) cell with
extremely long element life. The Tox-Refrig/ANA
transducer requires 24 vdc power and has a 4 to 20 mA
output current which is proportional to the refrigerant
gas concentration. The cover plate inside the expolsion
proof enclosure contains: test points (which are
receptables for voltage meter probes) for measurement
of sensor signal, heater voltage; visual indicator for
sensor check; and potentiometers adjustments for zero
and span.

BACKGROUND:

ANSI/ASHRAE Standard 15-1994, Safety Code for Mechanical Refrigeration, lays out requirements
for the monitoring of mechanical equipment rooms containing refrigeration equipment. Paragraph

8.13.2 reads in part:

“Each machinery room shall contain a detector, located in an area where refrigerant from a leak
will concentrate, which shall actuate an alarm and mechanical ventilation in accordance with

8.13.4 at a value not greater than the corresponding TLV-TWA (or toxicity measure consistent
therewith).”

FEATURES

• Sensitivity check indicator • Current output may be read as a

• Low voltage circuits voltage during calibration

• 4 to 20 on A output signal • Sensor failure indicator

• Meets ASHRAE Std. 15-1994 • Interfaces directly to DDC systems

• Explosion Proof Housing

TOXALERT INTERNATIONAL, Inc., PO Box 159, Mound, MN. 55364 PHONE: [phone] • FAX: [phone]

www.toxalert.com

Also paragraph 7.4.2, Rules:

“(d) detectors (refrigerant, oxygen, etc.) are located in area where refrigerant vapor leak will be concen­trated so as to provide warning at a concentration not exceeding the refrigerant(s) TLV-TWA (detectors
are not required for ammonia due to its self-alarming character);”

&

“(f) when the quantity of refrigerant, expect Groups A1 and B1 and ammonia exceeds Table 1 quantities,
the area shall be classified as a hazardous location and all electrical equipment shall conform to the
requirements of Class 1, Division 2, of the National Electrical Code. 9.”

Because of the requirements in Rule 3(f), all of Toxalert’s refrigerant sensors are supplied in an
explosion proof housing.

TABLE #1

*REFRIG. *SAFETY TLV AEL PEL
ID# CLASSIF. (PPM) (PPM) (PPM) IDHL

R-11 A-1 1000 1000
R-12 A-1 1000 1000
R-22 A-1 1000
R-113 A-1 ***C1000
R-123 B-1 30 1000
R-134a A-1 1000 1000
R-142b A-2 1000
R-152a A-2 1000
R-500 A-1 1000
R-502 A-1 1000 1000
**R-717(NH3)
AMMONIA B-2 25

* The Refrigerant designation number and Safety Classification are from ANSI/ASHRAE
Standards 34-1992.

** Toxalert has Ammonia Sensors to monitor for ammonia refrigerant (model TOX-NH

3

/ANA).

*** The concentration that should not be exceeded during any part of the working exposure.

TLV - Threshold Limit Value, established for industrial chemicals by American Conference of
Government Industrial Hygienists, is the time weighted average concentration of an airborn
chemical to which nearly all workers may be exposed during an 8 hour day, 40 hour week without
adverse effect.

TOXALERT INTERNATIONAL, Inc., PO Box 159, Mound, MN. 55364 PHONE: [phone] • FAX: [phone]

www.toxalert.com