ES-7502 Rev.16

B3HU

Space-saving Two-wire Signal
Conditioners B3-UNIT

2-WIRE UNIVERSAL TEMPERATURE TRANSMITTER

(HART communication, intrinsically safe)
Functions & Features
• Universal input: mV, V, T/C, RTD, resistance, potentiometer and DC voltage
• High accuracy
• HART communication
• Intrinsically safe approval
• Programming via hand-held communicator or via PC
• A wide variety of T/C and RTD types
• User’s temperature table can be used
• Self diagnostics
• Input-output isolated

MODEL: B3HU–[1]/A

ORDERING INFORMATION

• Code number: B3HU-[1]/A
Specify a code from below for [1].
  (e.g. B3HU-0/A)
• Use Ordering Information Sheet (No. ESU-7502). Factory standard setting will be used if not otherwise specified.
• Specify the country in which the product is to be used with the Safety Approval code 2.

[1] SAFETY APPROVAL

0: None
1: FM intrinsically safe
2: ATEX intrinsic safety

OPTIONS

CJC Sensor
/A: External Sensor (must be specified)

RELATED PRODUCTS

• USB interface Bell202 modem (model: COP-HU)
Usable in ‘non-hazardous’ area only.
• Hand-held communicator
(Consult HART Communication Foundation (HCF) web
site: www.hartcomm.org. )
• AMS (version 6.0 or higher)
• Simatic PDM (version 6.0 or higher)
• PC configurator software (model: B3HUCFG)
Downloadable at our web site.

GENERAL SPECIFICATIONS

Construction: Small-sized front terminal structure
Connection: Euro type connector terminal
(Applicable wire size: 0.2 - 2.5 mm2 (pin terminals: 0.2 - 1.5 mm2), stripped length 8 mm)
Housing material: Flame-resistant resin (gray)
Isolation: Input to output
Burnout (except DC voltage input): Upscale, downscale or no burnout selectable (standard: upscale);
Also detects wire breakdown and overrange input exceeding the electrical design limit for DC voltage input.
Cold junction compensation (T/C): CJC sensor (included) to be attached to the input terminals
User-configurable items:
• Input sensor type
• Number of wires (RTD & resistance)
• Input range
• Inverted output
• Burnout
• Damping time (via HART only, standard: 0)
• Sensor calibration (via HART only)
• Output calibration
• Special linearization data (via HART only)
• HART communication mode

HART COMMUNICATION

Protocol: HART communication protocol
HART address range: 0 – 15 (factory set to 0)
Transmission speed: 1200 bps
Digital current: Approx. 1 mAp-p when communicating
Character format: 1 Start Bit, 8 Data Bits, 1 Odd Parity Bit,
1 Stop Bit
Distance: 1.5 km (0.9 miles)
HART communication mode: Master-Slave Mode and Burst Mode (factory set to Master-Slave)
HART network mode: Point-to-Point Mode and Multi-drop Mode; automatically set to Multi-drop Mode when the address is set to other than 0.

INPUT SPECIFICATIONS

The input type is factory-set to K thermocouple, and the input range to 0 to 100°C.
See Table 1 for the available input type, the minimum span, and the maximum range.
■ DC mV & V
Input resistance: ≥ 1 MΩ
■ Thermocouple
Input resistance: ≥ 1 MΩ
Burnout sensing: 130 nA ±10 %
■ RTD (2-wire, 3-wire or 4-wire)
Excitation: 0.2 mA ± 10 %
Allowable leadwire resistance: Max. 20 Ω per wire
■ Resistance (2-wire, 3-wire or 4-wire)
Excitation: 0.2 mA ±10 %
Allowable leadwire resistance: Max. 20 Ω per wire
■ Potentiometer
Excitation: 0.2 mA ±10%
Allowable leadwire resistance: Max. 20 Ω per wire

OUTPUT SPECIFICATIONS

Output range: 4 – 20 mA DC
Operational range: 3.8 – 21.6 mA
Load resistance vs. supply voltage:
Load Resistance (Ω) = (Supply Voltage (V) – 12 (V))
÷ 0.024 (A)      (including leadwire resistance)

INSTALLATION

Supply voltage
 • 12 – 42 V DC (non-approved)
 • 12 – 28 V DC (approved)
Operating temperature: -40 to +85°C (-40 to +185°F)
(See Safety Parameters for use in a hazardous location.)
Operating humidity: 0 to 95 %RH (non-condensing)
Mounting: DIN rail
Weight: 80 g (2.8 oz)

PERFORMANCE

Accuracy: See Table 1 and ‘Explanations of Terms.’
Cold junction compensation error: ±0.5℃ (±0.9°F)
Temp. coefficient: ±0.015 %/°C (±0.008 %/°F) of max. span at -5 to +55°C [23 to 131°F]
Start-up time: Approx. 8 sec.
Response time: ≤ 2 sec. (0 – 90 %) with damping time
set to 0 and when not communicating via HART.
Supply voltage effect: ±0.003 % × [Output Span] / 1 V
Insulation resistance: ≥ 100 MΩ with 500 V DC
Dielectric strength: 1500 V AC @1 minute
(input to output to ground)

EXPLANATIONS OF TERMS

■ ACCURACY
This transmitter’s accuracy is theoretically defined as the addition of A/D and D/A conversion errors:

  Accuracy = A/D Conversion Error + D/A Conversion Error

The A/D conversion error means that measured as HART signal which is A/D converted from the analog input signal.
The D/A conversion error of this transmitter is relatively very small so that it does not really affect the unit’s overall performance.
The “Accuracies” given in Table 1 therefore equals the A/D conversion error.
The temperature drift (coefficient) or the cold junction compensation error is not included in the “Accuracy.”
■ CALCULATION EXAMPLES OF OVERALL ACCURACY IN %
• DC Voltage
1) 0 – 200 mV
Absolute value accuracy (Table 1): 40 μV
40 μV ÷ 200000 μV × 100 = 0.02 % < 0.1 %
➠ Overall accuracy = ±0.1% of span
2) 0 – 4 mV
Absolute value accuracy (Table 1): 10 μV
10 μV ÷ 4000 μV × 100 = 0.25 % > 0.1%
➠ Overall accuracy = ±0.25 % of span
• Thermocouple
1) K thermocouple, 0 – 1000°C
Absolute value accuracy (Table 1): 0.25°C
0.1% × 1000°C = 1°C > 0.25°C
CJC error (0.5°C) added: 1 + 0.5 = 1.5°C
1.5°C ÷ 1000°C × 100 = 0.15 %
➠ Overall accuracy including CJC error = ±0.15 % of span
2) K thermocouple, 50 – 150°C
Absolute value accuracy (Table 1): 0.25°C
0.1 % × (150 – 50)°C = 0.1°C < 0.25°C
CJC error (0.5°C) added: 0.25 + 0.5 = 0.75°C
0.75°C ÷ (150 – 50)°C × 100 = 0.75 %
➠ Overall accuracy including CJC error = ±0.75 % of span
• RTD
1) Pt 100, -200 – 800°C
Absolute value accuracy (Table 1): 0.15°C
0.15°C ÷ (800 – -200)°C × 100 = 0.015 % < 0.1 %
➠ Overall accuracy = ±0.1 % of span
2) Pt 100, 0 – 100°C
Absolute value accuracy (Table 1): 0.15°C
0.15°C ÷ 100°C × 100 = 0.15 % > 0.1 %
➠ Overall accuracy = ±0.15 % of span

STANDARDS & APPROVALS

EU conformity:
ATEX Directive 
  Ex ia EN 60079-11
EMC Directive 
  EMI EN 61000-6-4
  EMS EN 61000-6-2
RoHS Directive
Safety approval:
FM: Intrinsically safe
  Class I, Div. 1, Groups A, B, C and D
  Class I, Zone 0, AEx ia IIC
  T4 and T5
  (Class 3610)

SAFETY PARAMETERS

Operating temperature
For ATEX / FM:
  T4: -40 to +80°C
  T5: -40 to +55°C
Ex-data:
• Output circuit
  Ui (Vmax): 30 V DC
  Ii (Imax): 96 mA DC
  Pi (Pmax): 0.72 W
  Ci: 1 nF
  Li: 0 mH
• Sensor circuit
  Uo (Voc): 6.4 V DC
  Io (Isc): 30 mA DC
  Po: 48 mW
  Co (Ca): 20 μF
  Lo (La): 10 mH

INPUT TYPE, RANGE & ACCURACY

EXTERNAL DIMENSIONS & TERMINAL ASSIGNMENTS unit: mm [inch]

SCHEMATIC CIRCUITRY & CONNECTION DIAGRAM