High Speed Analogue Input Module
The EKE-Trainnet® High Speed Analogue Input Module (HSA) provides a standard interface for analogue input signals.
Signals can be current (-20…+20mA) and voltage (-10…10V). Separate channels are provided for frequency signal measurements with the capability to measure pulse-width ratio (PWM). The EKE-Trainnet® HSA converts the analogue signals and makes them available to the train computer’s Central Processing Unit (CPU) module. The EKE-Trainnet® HSA can be used as part of an EKE-Trainnet® Train Control and Management System, Vehicle Control Unit or Event Recorder.
Key Features
The EKE-Trainnet® HSA has 4 current channels and 4 voltage channels divided into four isolated groups. 4 frequency channels are also available.
The four frequency input channels can measure frequencies up to 16 kHz, period, pulse width, pulse count and rotary decoding with direction indication (compatible with most industry standard tachometers).
The four current measurement channels can measure currents between -20 and +20 mA. The module has the capability to supply voltage to external sensors or to supply loop voltage to the current loops. The module 4 voltage measurement channels can measure voltages between -10 and +10 V.
The module has its own 32-bit Floating point Digital Signal Processor (DSP) for high signal processing capability and uses factory calibration values to convert the measurement value to mV or µA with great accuracy. The embedded DSP processor can be used to perform signal processing tasks like filtering. It also implements diagnostics functions and reports to the system CPU module if it suspects that the input values cannot be trusted.
The resolution of the input A/D conversion is sign+12 bits, and the cut-off frequency of the hardware low pass filter is 150 Hz. Both current and voltage channels are capable of giving over range indications, which can be used for diagnostic purposes.
The module development is based on the railway standards EN 50126, EN 50716 (previously EN 50128) and EN 50129 in accordance with safety integrity level SIL 2. A non-SIL version of the module is also available.
