Specifications - HMT370EX

HMT370EX User Guide

Document code
M212305EN
Revision
E
Language
English
Product
HMT370EX
Document type
User guide
Table 1. Measurement performance
Property Description/value
Relative humidity
Measurement range 0–100 %RH

Accuracy at +23 °C (+73.4 °F) 1

±0.8 %RH (0–90 %RH)
Factory calibration uncertainty 2

±0.5 %RH (0–40 %RH)

±0.8 %RH (40–95 %RH)

T63 response time 15 s
Sensor options

HUMICAP® R2

HUMICAP® L2

Temperature
Measurement range −70 … +180 °C (−94 … +356 °F)

Accuracy at +23 °C (+73.4 °F) 1

±0.1 °C (±0.18 °F)
Factory calibration uncertainty 2 ±0.1 °C (±0.18 °F) at +23 °C (+73.4 °F)
Sensor Pt1000 RTD Class F0.1 IEC 60751
Other available measurement parameters
Dew point temperature, dew point / frost point temperature, absolute humidity, mixing ratio, wet-bulb temperature, water concentration, water vapor pressure, water vapor saturation pressure, enthalpy, dew point temperature difference, absolute humidity at NTP, water mass fraction, relative saturation, water activity, water concentration in mineral transformer oil, water concentration in JET A-1 fuel, saturation temperature
Figure 1. Humidity measurement accuracy as function of temperature
Figure 2. Temperature measurement accuracy over full range

HUMICAP® 180L2 sensor option

The HUMICAP® 180L2 sensor is used in the HMP378F and HMP378H probe variants that are intended for oil and JET A-1 fuel measurements.

Table 2. HUMICAP® 180L2 measurement performance
Property Description/value
Water activity
Measurement range 0–1 aw 1
T90 response time 2 10 min
Sensor HUMICAP® 180L2
Accuracy 3

±0.01 aw (±1 %RS)

Factory calibration uncertainty

±0.6 %RH (0–40 %RH)

±1.0 %RH (40–95 %RH)

Temperature
Measurement range −40 … +180 °C (−40 … +356 °F)
Accuracy at +20 °C (+68 °F) ±0.2 °C (0.36 °F)
Figure 3. Aw measurement accuracy
Table 3. HMP378F and HMP378H ppm accuracy
Property Value
JET A-1 fuel ppm accuracy (HMP378H) 6 ±15 % of the reading (typical)
Moisture in transformer oil ppm accuracy (HMP378F) 7 ±10 % of the reading (typical)
Table 4. Operating environment
Property Description/value
Operating temperature for electronics -40 … +60 °C (-40 … +140 °F)
Operating temperature with display -20 … +60 °C (-4 … +140 °F)
Storage temperature -40 … +70 °C (-40 … +158 °F)
Pressure range See probe specifications
Note: Do not install the LCD display model in a location where the transmitter is exposed to direct sunlight.
Table 5. Compliance
Property Description/value

Electromagnetic compatibility (EMC)

EN 61326‑1, industrial environment

Compliance marks

CE, China RoHS, RCM
Table 6. Inputs and outputs
Property Description/value

Operating voltage

12–28 V

Analog outputs

2 outputs (two-wire, 4–20 mA)

Connection via safety barriers

Typical accuracy of analog outputs at +20 °C ±0.0625 % full scale
Typical temperature dependence of analog outputs 0.005 % / °C (0.005 % / °F) full scale
Transmitter service port connection USB cable 219690
Probe service port connection USB cable USB2
Display options
  • Graphical LCD display
  • Model without display 8
Table 7. Mechanical specifications
Property Description/value
Connections Screw terminals, 0.33–2.0 mm2 wires (AWG 14-22)
Cable glands M20×1.5
Conduit fitting NPT 1/2" and M16
Housing material EN AW-6082
Housing weight

LCD transmitter: 1500 g (3.3 lb)

LED transmitter: 1520 g (3.35 lb)

HMP371 fixed probe: 320 g (0.7 lb)

IP rating

With probe connected to the transmitter: IP66
With probe detached from the transmitter: IP54
Figure 4. HMT370EX transmitter dimensions
Table 8. Ex classifications by region
Property Description/value
NOTE: The Ex classifications show the highest level of compliance. Although lower compliance levels are not shown in the classification, they are also included in the classification. For example, compliance with Division 1 also means compliance with Division 2, and compliance with Zone 0 also means compliance with Zone 1 and Zone 2.
Europe (ATEX)

Gas classification

EU (2014/34/EU)

II 1 G Ex ia IIC T4 Ga

Dust classification

II 1 D Ex ia IIIC T200 85 °C Da

Safety factors

Ui = 28 VDC, Ii = 100 mA, Ci = 12.1 nF, Pi = 700 mW, Li = 16 μH

Environmental specifications
Tamb -40 … +60 °C (-40 … +140 °F)
Pamb 0.8 … 1.1 bar
International (IECEx)
Gas classification

Ex ia IIC T4 Ga

Dust classification II 1 D Ex ia IIIC T200 85 °C Da
Safety factors

Ui = 28 VDC, Ii = 100 mA, Ci = 12.1 nF, Pi = 700 mW, Li = 16 μH

Environmental specifications
Tamb -40 … +60 °C (-40 … +140 °F)
Pamb 0.8 … 1.1 bar
Japan (CML)
Ex classification

Ex ia IIC T4 Ga

Ex ia IIIC T200 85°C Da

CML 21JPN2417X

China (NEPSI)
Ex classification

Ex ia IIC T3~T6 Ga

GYJ21.1325X

Korea (KCs)
Ex classification

Ex ia IIC T4 Ga

Ex ia IIIC T200 85 °C Da

-40 °C ≤ Tamb ≤ +60 °C

IECEx EESF 20.0044.X

21-KA4BO-0891X, 21-KA4BO-0892X

US (FM)
Ex classification

Class I, Zone 0, AEx ia IIC T4 Ga

Zone 20, AEx ia IIIC T85°C Da

IS Class I, Division 1, Groups A, B, C, and D T4

IS Class II, III, Division 1, Groups E, F, and G T85°C

CAN (FM)
HMT370EX equipment rating

Intrinsically safe for:

Class I, II, III Division 1, Groups A, B, C, D, E, F, and G, T4

Class I, Zone 0, Ex ia IIC T4

Zone 20, Ex ia IIIC Temperature Code T85°C

Ta: -40 °C to +60 °C;

IP54 (transmitter alone)

IP66 (transmitter with the probe body attached)

UK (UKEX)
Ex classification

II 1 G Ex ia IIC T4 Ga

II 1 D Ex ia IIIC T200 85 °C Da

−40 °C ≤ Tamb ≤ +60 °C

CML 21UKEX2316X

1 Defined against calibration reference. Including non-linearity, hysteresis, and repeatability.
2 Defined as ±2 standard deviation limits. Small variations possible; see calibration certificate.
3 0–1 aw corresponds to 0–100 %RH
4 At +20 °C (+68 °F) in still oil.
5 In range 0–0.5 aw, including non-linearity, hysteresis, and repeatability. See accuracy graph below.
6 For more information on HMP378H measurements, see HMP378H probe option for measuring JET A-1 fuel moisture and temperature
7 Note: valid for mineral transformer oil. For more information on HMP378F measurements, see HMP378F probe option for measuring oil moisture and temperature
8 Recommended when the transmitter is exposed to direct UV light, and for outdoor installations and high-humidity environments.