Fieldpiece ATWB1 User manual

K-type, Clip-on
Wet Bulb
Thermocouple
Model: ATWB1
Max: 150ºF
OPERATOR’S MANUAL
Description
The ATWB1 is an inexpensive and effective way
to take a wet bulb measurement. The ATWB1 is
equipped with a durable hydrophilic sock specifical-
ly designed for wet bulb measurements. Increasing
the reliability in the wet bulb measurements. The
alligator clip allows the user to affix the ATWB1 to a
fixed surface, such as a vent, allowing the user to
take hands free measurements. The ATWB1 also
comes with a wrap tab making it easy to wind and
store the thermocouple.
The ATWB1 K-type thermocouple can be used
continously to take temperature readings up to
150ºF. The ATWB1 can be used with any ther-
mometer which accepts a K-type thermocouple.
Operation
To use the ATWB1 plug it into any thermometer
accepting a K-type thermocouple. Then submerge
socked probe tip under water until it is fully saturat-
ed and placeATWB1 probe in air flow. The wet bulb
reading will be the lowest reading before the tem-
perature rises back up. You can use a thermome-
ter’s MIN function to make it easy.
Calibration
Due to variances in the thermocouple wire and
other parts of the system, a field calibration should
be conducted before use. Field calibration typically
gives +/- 1ºF overall accuracy. The instructions for
this calibration should be in the operating manual
for the thermometer.
Broken Wires:
Due to frequent bending, the K-type thermocou-
ple wire may break or come loose, typically near the
plug. To repair, cut and strip the thermocouple wire
near the plug. The red wire is the (-) wire and it
belongs on the wider plug. Loosen the screws on
plugs and wind the conductors around the appropri-
ate screws and tighten. Finally, position the plugs
into the tab and screw the tab back together.
Specifications
Thermocouple: K-type Nickel Chromium/Nickel
Aluminum.
Accuracy: -50ºF to 150ºF +/- 4ºF,
Range: -50ºF to 150ºF max continuous operation.
Probe insulation: While wire insulation may be
designated for higher temperatures, due to the
flamability of the wet sock we recommend that a
maximum measured temperature of 150ºF.
Plug: K-Type Thermocouple male mini plug.
Warranty
The ATWB1, K-Type, clip-on thermocouple is
warranted against manufacturer’s defects for one
year. This warranty does not apply to defects result-
ing from abuse, neglect, accident, unauthorized
repair, alteration, or unreasonable use of the instru-
ment. Any implied warranty arising out of the sale of
Fieldpiece's products including but not limited to
implied warranties of merchantability, and fitness for
purpose, are limited to the above. Fieldpiece shall
not be liable for incidental or consequential dam-
ages.
Service
Return any defective ATWB1 to Fieldpiece for
warranty service along with proof of purchase.
Contact Fieldpiece for out of warranty repair
charges.
Fieldpiece Instruments, Inc.
California, U.S.A.
www.fieldpiece.com
WARNINGS
When testing hot temperatures, the thermocouple
and metal alligator clip may become hot. Do not handle
the thermocouple or the metal clip when hot.
!
!
K-type, Clip-on
Wet Bulb
Thermocouple
Model: ATWB1
Max: 150ºF
OPERATOR’S MANUAL
Description
The ATWB1 is an inexpensive and effective way
to take a wet bulb measurement. The ATWB1 is
equipped with a durable hydrophilic sock specifical-
ly designed for wet bulb measurements. Increasing
the reliability in the wet bulb measurements. The
alligator clip allows the user to affix the ATWB1 to a
fixed surface, such as a vent, allowing the user to
take hands free measurements. The ATWB1 also
comes with a wrap tab making it easy to wind and
store the thermocouple.
The ATWB1 K-type thermocouple can be used
continously to take temperature readings up to
150ºF. The ATWB1 can be used with any ther-
mometer which accepts a K-type thermocouple.
Operation
To use the ATWB1 plug it into any thermometer
accepting a K-type thermocouple. Then submerge
socked probe tip under water until it is fully saturat-
ed and placeATWB1 probe in air flow. The wet bulb
reading will be the lowest reading before the tem-
perature rises back up. You can use a thermome-
ter’s MIN function to make it easy.
Calibration
Due to variances in the thermocouple wire and
other parts of the system, a field calibration should
be conducted before use. Field calibration typically
gives +/- 1ºF overall accuracy. The instructions for
this calibration should be in the operating manual
for the thermometer.
Broken Wires:
Due to frequent bending, the K-type thermocou-
ple wire may break or come loose, typically near the
plug. To repair, cut and strip the thermocouple wire
near the plug. The red wire is the (-) wire and it
belongs on the wider plug. Loosen the screws on
plugs and wind the conductors around the appropri-
ate screws and tighten. Finally, position the plugs
into the tab and screw the tab back together.
Specifications
Thermocouple: K-type Nickel Chromium/Nickel
Aluminum.
Accuracy: -50ºF to 150ºF +/- 4ºF,
Range: -50ºF to 150ºF max continuous operation.
Probe insulation: While wire insulation may be
designated for higher temperatures, due to the
flamability of the wet sock we recommend that a
maximum measured temperature of 150ºF.
Plug: K-Type Thermocouple male mini plug.
Warranty
The ATWB1, K-Type, clip-on thermocouple is
warranted against manufacturer’s defects for one
year. This warranty does not apply to defects result-
ing from abuse, neglect, accident, unauthorized
repair, alteration, or unreasonable use of the instru-
ment. Any implied warranty arising out of the sale of
Fieldpiece's products including but not limited to
implied warranties of merchantability, and fitness for
purpose, are limited to the above. Fieldpiece shall
not be liable for incidental or consequential dam-
ages.
Service
Return any defective ATWB1 to Fieldpiece for
warranty service along with proof of purchase.
Contact Fieldpiece for out of warranty repair
charges.
Fieldpiece Instruments, Inc.
California, U.S.A.
www.fieldpiece.com
WARNINGS
When testing hot temperatures, the thermocouple
and metal alligator clip may become hot. Do not handle
the thermocouple or the metal clip when hot.
!
!
v06
v06

Relative Humidity (%RH)
Relative humidity is often found to help evaluate
air comfort or to find the target superheat of an air
conditioning system. There are a few ways to find
%RH. You can use an accessory head like the
ARH4 to measure %RH, wet bulb, dew point or dry
bulb directly. You could also use an actual sling psy-
chrometer, or use the ATWB1 wet bulb thermocou-
ple and a typical dry bulb thermocouple with the
chart to the left.
Relative Humidity (%RH)
Relative humidity is often found to help evaluate
air comfort or to find the target superheat of an air
conditioning system. There are a few ways to find
%RH. You can use an accessory head like the
ARH4 to measure %RH, wet bulb, dew point or dry
bulb directly. You could also use an actual sling psy-
chrometer, or use the ATWB1 wet bulb thermocou-
ple and a typical dry bulb thermocouple with the
chart to the left.
50 52 54 56 58 60 62 64 66 68 70 72 74 76
55 71 82 94
60 49 58 68 78 89 100
65 32 40 49 57 66 75 85 95
70 20 27 34 41 48 56 64 73 81 91 100
75 11 17 22 28 35 41 48 55 63 70 78 87 96
80 4 9 14 19 24 30 36 42 48 54 61 68 76 84
85 3 7 12 16 21 26 31 36 42 48 54 60 67
90 2 6 10 14 18 23 27 32 37 42 48 53
95 2 5 9 12 16 202428333742
100 2 5 8 11 151822252934
105 2 4 7 101316202327
110 2 4 7 9 12 15 18 21
115 2 4 6 9 11 14 16
Relative Humidity (%RH)
Dry Bulb Temperature (°F)
Wet Bulb Temperature °F
50 52 54 56 58 60 62 64 66 68 70 72 74 76
55 71 82 94
60 49 58 68 78 89 100
65 32 40 49 57 66 75 85 95
70 20 27 34 41 48 56 64 73 81 91 100
75 11 17 22 28 35 41 48 55 63 70 78 87 96
80 4 9 14 19 24 30 36 42 48 54 61 68 76 84
85 3 7 12 16 21 26 31 36 42 48 54 60 67
90 2 6 10 14 18 23 27 32 37 42 48 53
95 2 5 9 12 16 202428333742
100 2 5 8 11 151822252934
105 2 4 7 101316202327
110 2 4 7 9 12 15 18 21
115 2 4 6 9 11 14 16
Relative Humidity (%RH)
Dry Bulb Temperature (°F)
Wet Bulb Temperature °F