Data sheet. Technical data

Transcription

1 Description 4 galvanically isolated analog channels, each configurable as a counter input as well. Data transmission via galvanically isolated CAN bus with a maximum sample rate of 2 ksamples per channel. Technical data Supply voltage 6-50 V DC Power consumption < 1,9 W Inputs galvanically isolated Isolation, channel to channel 500 V Isolation, channel to supply 500 V Isolation, CAN to supply 500 V Operating temperature C C Operating temperature HT -40 C C Storage temperature -55 C C Humidity 0 100% rel. humidity Dimensions 110 x 40 x 32 mm Weight 160 g Measurement ranges (+/-) 25, 100, 200, 500 mv; 1, 5, 10, 20, 60 V Maximum input voltage 100 V Sample rate CAN (per channel) 1, 2, 5, 10, 20,100, 200, 500, 1000, 2000 Hz (limited by the CAN bandwidth) Sample rate selected by either by configuration tool or CAN command Resolution 16 Bit CAN data format 16 Bit (skaled to the measurement range) Filter Butterworth 3rd order analog filter plus a digital CIC4+ FIR/IIR filter Filter: DC Offset < 0.05 % Filter: DC gain ± Measurement range as counter module 0,02 Hz - 20 khz with TTL level or 0 / 10 V square wave input Page 1 of 14

2 Single channel input Tiefpass Messbereichsumschaltung Kanal 1 Digital/CAN Isolation Verstärker Isolation 16 Bit ADC FPGA CPU CANTransceiver DC/DC Wandler = Kanal 4 = Kanal 1 DC/DC Wandler = = Kanal 4 Page 2 of 14

3 Input resistance Range Input resistance 60 V ca. 2,1 MΩ 20 V ca. 2,2 MΩ 10 V ca. 2,5 MΩ 5V ca. 3,2 MΩ 1V > 10 GΩ 500 mv > 10 GΩ 100 mv > 10 GΩ 25 mv > 10 GΩ LED-Status display POWER on Module is supplied with power RUN on Module sends data flashe An error occurred. The actual error state may be s determined via the CCPKonfig. off Severe error. No detailed output possible, module is bus-off. Page 3 of 14

4 Connector pinout CAN: 6pole Fischer QIC HT Pin Signal 1 CAN H 2 CAN L 3 Supply + 4 Supply + 5 Supply - 6 Supply - Analog: pole Lemo: EEG.1K.308.CLN Pin Signal 1 Channel Channel 1-3 Channel Channel 2-5 Channel Kanal 3-7 Channel Channel Page 4 of 14

5 Low pass filter The CAETEC analog module is equipped with a selectable DSP low pass filter module in addition to the analog antialiasing prefilter. This module permits the user to select the optimum filter for his measurement task. The filter is implemented so that the corner frequencies are a fixed percentage of the send rate of the channel. This feature allowed to implement high-order filters with corner frequencies in the vicinity of the Nyquist frequency for every single send rate the module has to offer. Selectable filter settings Filter off: the digital filter is turned off, the Signal input is passed only through the antialiasing filter and the CIC sample rate changer. The signal propagation time is reduced to the absolute minimum, but frequencies higher than half the send rate will be seen at their image frequency. Fast FIR filter: Short signal transition time and about 10 db dampening at the Nyquist frequency. Constant group delay by design. The digital counterpart of a Bessel filter. Slow FIR filter: Long signal transition time, but 50 db dampening at the Nyquist frequency. Constant group delay by design. The digital counterpart of a Bessel filter. Butterworth filter: 8th order filters with transition frequencies of approx. 15, 30, 35, 40 and 45% of the send rate. Main characteristic of a Butterworth filter is its highly linear frequency response in the passband while the drop-off in the stopband is comparatively slow. Chebyshev filter: 8th order filters with transition frequencies of approx. 30, 35, 40 and 45% of the send rate.and a ripple of less than 0,05 db in the passband. Chebyshev filter are steeper than Butterworth filters at the cost of some ripple in the passband. Elliptical filter 8th order filters with transition frequencies of approx. 15, 30, 35, 40 and 45% of the send rate and a design stopband dampening of > 80 db. Very steep filter with highly nonlinear dampening in the stopband. Filter characteristics: (see next pages) Page 5 of 14

6 Butterworth filter: Page 6 of 14

7 Chebyshev filter: Page 7 of 14

8 Elliptical filter: Page 8 of 14

9 No filter / FIR filter: The phase angel of a FIR filter is frequency-independent. Page 9 of 14

10 Counter mode The analog module has a frequency counter mode as well. The resolution of the counter depends on the CAN sampling rate and the input frequency: Graph1: Resolution of the frequency measurement Page 10 of 14

11 Settings If used as counter the following settings are used: On: Setting thecheckmark will configure this channel as a frequency counter. Only available if the checkmark in the analog configuration was cleared first. Channel: Channel Number within a module not editable. Name: A user definable arbitrary text. May only include letters, numbers and the "_" character. ID: CAN-Identifier of the CAN-message. Bitoffset: The offset of the first bit within the CAN message. The CCPKonfig only accepts whole bytes as bitoffset. If channels are configured so that bits within a CAN message would be used by several channels the channel with the lower number will use the bits while the channel(s) with the higher number(s) are switched off, i.e. they won't send anything. Sample rate: CAN message transmission rate. Sensor supply: Adjustable output voltage for external sensors. Switchable between ±5 V, ±8 V, ±10 V, ±12 V, ±15 V and ±20 V. Trigger level: Voltage at which the modules determines between logic high and low. Adjustable between -55 V and 55 V. Hysteresis: Dead band between "low"- and "high"-level to prevent false trigger detection due to input noise. Adjustable between 0,1 V and 20 V. Pulse filter: Adjustable dead band to filter spurious short signal spikes. Adjustable between 0 and 75 μs in steps of 5 μs. Predivider: Switchable divider to compensate for rotary decoders with non-equal trigger distribution. Adjustable between 1 and 16. Timeout: Time after which the module transmits zero if no further pulses are detected. Adjustable between 1 ms and 65 s. Offset: For post calculation (stored within the DBC file). Doesn't effect the value sent via the CAN bus. Scale: For post calculations (stored within the DBC file). Doesn't effect the value sent via the CAN bus. Page 11 of 14

12 Sampling rate as counter 200 khz = 5 us Pulsfilter set to 1 => 2. sukzessive values outside of the hysteresis band trigger the counter Hysteresis Pulse filter set to 1 (= 5µs) => a single value outside the hysteresis band is ignored Sample point Signal "low" Sig nal Trigger level Signal undefined => no change Signal "high" Graph2: Counter parameters explained (I) Function of the predivider Example: blower n = 6000 UPM = 100 Hz 4 Blades. 1) Symmetric distribution of the blades - angle 0 / 90 Predivider set to 1: Counter output 400 Hz. Predivider set to 2: Counter output 200 Hz. 2) Asymmetric distribution ex. angle 0 / 45 Predivider set to 1: Counter output 800 Hz / 270 Hz, depending on the last blades which passed the sensor Predivider set to 2: Counter output always 200 Hz. Graph 3: Counter parameters explained (II) Page 12 of 14

13 Sample rate switching by CAN command Tha sample rate of the analog channels may be switched during the measurement. This is done via a CAN command with a selectable identifier. Preparing the module To enable sample rate switching the ID of the switching command has to be set via the CCPKonfig tool: select the module, and choose module settings in the main window. A new window opens where the CAN ID for the sample rate switching command may be set Description of the CAN command for the sample rate switching The CAN command is always 8 Bytes long and is formatted as follows: Byte 1 Byte 2 Byte 3 Byte 4 Channel mask (32 Bit Bitfield) Byte 5 Byte 6 Send rate (Hz) Byte 7 Byte 8 Duration (s) Channel mask Byte 1 Byte 2 Byte 3 Byte Channel number All values are little endian (Bit 0-7; Bit 8-15; Bit 16-23; Bit 24-31). Channel mask: Bitfield which determines the channels for which the command is valid (bits set to 1). other channels aren't reset, so several consecutive commands may be set for different sampling rates and durations. Send rate: INT16 of the new sample rate in Hz. Valid values are 1,2,5,10,20,50,100,200,500, 1000 and 2000 Hz. Other values are ignored. Different sampling rates may be set or every single channel by using appropriate channel masks. Duration: The time in seconds until the module falls back to the sampling rate set by the CCPKonfig. If this value is set to 0 the module will send with the new sample rate until it's either switched off or receives another sample rate switching command for the channel. Example: CAN-message C8 00 F4 01 (Hex) : h = b: Channel 1 and 3 are selected. 00C8h = 200d: New send rate 200 Hz. 01F4h = 500d: the new send rate is valid for 500 s. After that time it switches back to Page 13 of 14

14 the values set by the CCPKonfig. Page 14 of 14