Laurel Electronics LTA DPM SERIES ANALOG INPUT - Manual (Page 4)

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3. INTRODUCTION, 4-20 MA “DPM” SERIES TRANSMITTERS
This manual covers DIN rail transmitters with a 4-20 mA, 0-20 mA or 0-10V output and an analog
input. The transmitters duplicate the signal conditioning and signal processing features of 1/8 DIN
size, digital panel meter (DPM) counterparts for exceptional accuracy at high read rate.
The current and voltage transmitter outputs are jumper selectable and are transformer isolated to
avoid ground loops. The ultra-linear digital to analog converter (DAC) provides 16-bit resolution.
The output is scaled in software and tracks an internal linearized digital reading. Output accuracy
is ±0.015% of span for all DC analog input signals and ±0.15% of span for AC rms.
A wide range of analog signal sources are accommodated by five signal conditioners:
• DC input for volts, amps, process signals (e.g., 4-20 mA), and strain gauges. Most sensitive
full scale input range of 200 mV. Built-in 5A current shunt.
• AC rms input for volts and amps. Can be AC or DC coupled. Built-in 5A current shunt.
• Load cell or microvolt input with selectable full scale input ranges from 20 mV to 500 mV.
• Thermocouple temperature input for seven thermocouple types.
• RTD temperature or Ohms input for Pt100, Ni120 or Cu10 RTDs, 20Ω to 200 kΩ resistance.
An isolated transducer excitation output is standard. Three output levels are jumper selectable:
5V at 100 mA, 10V at 120 mA, or 24V at 50 mA. The factory default setting is 10V and can power
up to four 350 ohm load cells in parallel.
Dual solid state relays are standard. These are rated 130 mA at 140 Vac or 180 Vdc.
Serial communications are standard. RS232 or RS485 (half or full duplex) are user selectable via
jumpers and at the connector. The same factory default jumper setting is for RS232 and full
duplex RS485.
Isolation to 250V rms is provided for power, signal input, analog output, relay outputs, and com-
munications. Isolation adds safety and avoids possible ground loops. The transducer excitation
output is isolated to 50V from signal ground.
Internal jumpers are used to select the signal range, communication type, and excitation level.
The transmitter configuration is specified by the model number on the transmitter label. A user
can reconfigure the transmitter by opening the case and moving jumpers, as explained in this
manual.
Transmitter scaling is via serial connection to a PC using MS Windows based Instrument Setup
Software, which can be downloaded at no charge. The required transmitter-to-PC interface cable
is available for purchase.