Testo-6621 Temperature and humidity transmitter

testo 6621 – A01/A03 (wall version)

testo 6621 – A02 (duct version)

Parameters

Humidity

Meas. range

0 to 100% RH (>90% RH only briefly)
(not for high humidity processes)

Accuracy*

±2.0 %RH (0 to 90 %RH),
±4 %RH (90 to 100 %RH)

Temperature dependency/coefficient

Temperature coefficient: 0.05%/K
(gap of 25 °C/77 °F)

Sensor

Testo humidity sensor

Replaceability of sensor

Through Testo Service

Can be done by customer (s. below, Replacement sensors), subsequent 2-point adjustment required

Temperature

Meas. range

0 to +60 °C
(+32 to +140 °F)

-20 to +70 °C
(-4 to +158 °F)

Accuracy

±0,5 °C / 0,9 °F

Sensor

Active signal output: NTC
Passive signal output: NI1000

Inputs and outputs

Analog outputs

Number of channels

2 channels (humidity and temperature)

Output type

4 to 20 mA (2-wire)
0 to 1/5/10 V (4-wire)

Measuring rate

1/s

Accuracy of analog outputs

4 to 20 mA ±0,05 mA
0 to 1 V ±2,5 mV
0 to 5 V ±12,5 mV
0 to 10 V ±25 mV

Power

Voltage supply

20 to 30 V AC/DC

Current consumption

Output

Voltage supply [V]

Current consumption [mA]

2-wire current 4 to 20 mA

20
24
30

20
20
30

4-wire voltage 0 to 10V

24
30
20
24
30

7
7
20
22
28

General

Housing

Material / colour

ABS/
pure white (RAL 9010) or light grey

Dimensions

81 x 81 x 26 mm

81 x 81 x 42 mm
see drawing for probe

Weight

80 g / 90 g (A03)

160 g

Display

Display

2-line LCD (optional)

Resolution

Humidity: 0.1 %RH
Temperature: 0.1 °C/°F

Operation

Parameterization

P2A software

Assembly

Cable screw connection

None (cable routed through rear wall opening or break-out opening on bottom)

1 x M16 x 1,5

Other features

Protection class

IP30

IP65

EMC

According to EC directive 2004/108/EEC

Interfaces

1x mini-DIN for connecting PC

Reaction time

t90: < 15 s at 2 m/s;
For calibration and adjustment, please note:
The response time may be considerably higher in static air

Scaling range

-50 to 100 °C / -58 to 212 °F,
0 to 100 %RH

Operating conditions

Electronics temperature (housing) (with/without display)

0 to +60 °C/32 to +140 °F (A01/A03),
With display: 0 to +50 °C/+32 to +122 °F;
-20 to +70 °C/-4 to +158 °F (A02),
With display: 0 to +50 °C/+32 to +122 °F

Storage temperature

-40 to +70 °C (-40 to +176 °F)

Measuring medium

Air in air-conditioning systems or air-conditioned rooms