News Release

iC-RC1000: Analog monitoring of sine/cosine encoders for SIL and high speeds 06.12.2011
Easy retrofitting of safety requirements for sine/cosine position sensors
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iC-RC1000 acts as an analog watchdog IC for industrial controllers and drive systems in the evaluation of sine encoders for SIL applications. From standstill to high speeds two diagnostic channels monitor the encoder signals to check whether they keep to the 1 V specification, signaling OK or ERROR to the controller independently of one another for safe error detection with the minimum circuitry.

The FMEA-based architecture of iC-RC1000 has the necessary intrinsic safety required for SIL, enabling errors to be securely identified through redundancy. It is now possible to implement the required plausibility check of the line signals and cable connection parallel to the process channel without the need for additional A/D converters and safety-critical controller software.

iC-RC1000 monitors up to four signal lines for the correct DC voltage and the differential signal amplitude of two paired lines to see whether these remain within the specified range of 0.8 Vpp to 1.2 Vpp. An analog circuit derives the Lissajous curve from the sine and cosine signal and comparators monitor the vector length in real time. Any error indication is lengthened to at least 4 ms so that the controller can reliably detect an interrupt. The diagnostic outputs permit optocouplers to be directly connected up for galvanic isolation.

Safety watchdog iC-RC1000 can be used in the following applications:

SIL-compatible linear and rotary encoders
Encoder interfaces with SIL monitoring of sine/cosine inputs
Redundant functions monitoring in robot and handling systems
Test and monitoring units for sine/cosine encoders
Detection of cable breakages for PLC and controller inputs.

iC-RC1000 is designed for use at operating temperatures of -40C to 110C and operates on a supply voltage of 5 V. A 1.4 mA supply is typically sufficient for the two diagnostic channels which can be supplied by either one common or two separate power supplies and which monitor one another. The device is protected against ESD and is overvoltage-proof up to 36 V at the front end thanks to an internal clamp circuit.
Product iC-RC1000
Press Release iC-RC1000 (PDF) (254 kb)
Presseinformation iC-RC1000 (PDF) (255 kb)
 
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