SFPCI-6355 card isolated relay switch input and output cards. 4-channel SPDT (C) 4-channel SPDT relay output (A type) and 8-channel isolated digital input, each channel relay output has LED indicator. Indicator lights in the set state, otherwise it will vanish. Latch output state can be read back. 8-channel optically isolated digital input can be with the rising edge of the input pulse application host interrupt. Suitable for digital input in noisy environments or with floating potentials. Switch output with clear function on power. Warm start to keep the relay working status of this function can be maintained the relay output value, to ensure that the host restart unexpectedly malfunction of the dangers posed by over-voltage protection up to 70V input signal and high-voltage isolation of up to 3000V input channels, provide security guarantees for the application site; suitable for industrial control field and laboratory.