Products Catalog

Specification

Description
HD 788TR1, HD 788TR1-I, HD 786TR1, HD 988TR1, HD 988TR1-I and HD 988TR2 are 4÷20
mA transmitters with a microprocessor, configurable for Pt100 Platinum temperature sensors.
They convert the temperature variations found with any standard Pt100 sensor (100© at 0°C)
into a linear current signal with two leads in the field 4÷20 mA. Linearisation with a digital
technique allows excellent precision and stability to be obtained. The user can set the 4÷20
mA output (or 20÷4 mA) in any temperature range within the field -200...+650°C, with a
minimum amplitude of 25°C; it may be simply reprogrammed by pressing a key, without any
need to regulate jumpers, potentiometers, software, etc. A led indicates any alarm situations
(temperature outside the set range, broken or short-circuiting sensor) and assists the user
in the programming phase. The 4÷20mA output of models HD788TR1-I and HD988TR1-I
is galvanically isolated from the Pt100 input. The transmitters are also protected against
inversions of polarity. The HD 788TR1, HD 788TR1-I are specifically designed for installing in
type DIN B connecting heads, while the HD 988TR1, HD988TR1-I and HD 988TR2 are suitable
for fitting in containers with a 35 mm DIN bar connection. As well as the 4÷20 mA output, the
HD 988TR2 has a convenient 3½ digit display (height 10 mm) which allows the display of the
measured temperature. Suitable for fitting on the wall.
Technical data (20°C and 24V DC)
INPUT
HD 788TR1 - HD 788TR1-I
HD 786TR1
HD 988TR1 - HD 988TR1-I
HD 988TR2
Sensor Pt100 (100©)
Connection 3 (or 2) leads
Linearisation EN 60751, IEC 751
BS 1904 (±=0,00385)
Current in the sensor RLMax = 680 © @ Vcc = 24 Vdc
Red led Lights up during the programming phase and when
the measured temperature is outside the set range
Input-Output isolation (from
models HD 788TR1-I and HD
988TR1-I)
500 Vdc
Order codes
HD 788TR1: 4÷20 mA/20÷4 mA temperature transmitter for Pt100 sensor with 2 or 3 leads
configurable in the range -200...+650°C with minimum amplitude range 25°C, in a
container for DIN B 43760 heads.
HD 788TR1-I: 4÷20 mA/20÷4 mA isolated temperature transmitter for Pt100 sensor with 2
or 3 leads configurable in the range -200...+650°C with minimum amplitude range 25°C,
in a container for DIN B 43760 heads.
HD 786TR1: 4÷20 mA/20÷4 mA temperature transmitter for Pt100 sensor with 3 leads
configurable in the range -200...+650°C with minimum amplitude range 25°C. Suitable
for fitting on the wall.
HD 988TR1: 4÷20 mA/20÷4 mA temperature transmitter for Pt100 sensor with 2 or 3 leads
configurable in the range -200...+650°C with minimum amplitude range 25°C, in a
container for 35 mm DIN bar connection, dimension 1 module.
HD 988TR1-I: 4÷20 mA/20÷4 mA isolated temperature transmitter for Pt100 sensor with 2
or 3 leads configurable in the range -200...+650°C with minimum amplitude range 25°C,
in a container for 35 mm DIN bar connection, dimension 1 module.
HD 988TR2: 4÷20 mA/20÷4 mA temperature transmitter for Pt100 sensor with 2 or 3
leads configurable in the range -200...+650°C with minimum amplitude range 25°C, in
a container for 35 mm DIN bar connection, dimension 2 modules, with 3½ digit display,
height 10 mm.