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USB DIO High Voltage and Relay

Features

I/O Module Type Switch

USB-SSR Series devices have an onboard switch to configure

each module group for either input or output.

Devices are shipped with all modules configured for output.

Input and output modules cannot be mixed within a group.

Positive and negative relay contacts are brought out to screw

terminals for field wiring connections.

Relay Configuration Switche

USB-ERB/USB-SSR Series Only

USB-SSR Series and USB-ERB Series devices have two onboard

switches for configuring the relay logic polarity and output relay

power-up state for each relay bank/SSR module group. The cur-

rent configurationof each switch can be read back with software.

Devices are shipped with all relay banks/module groups confi -

ured for non-inverted logic and pull-up (relays/modules inactive

on power-up).

Differential Isolated Digital Inputs

USB-PDISO8 Series Only

All eight inputs on USB-PDISO8 Series devices can be driven by

either AC (50 Hz to 1000 Hz) or DC voltage, and can be read

back as a single byte.

Each input has a software-selectable filter with a time constant

of 5 ms (200 Hz). The filter is required for AC inputs, and recom-

mended for most DC inputs.

Each module group can be set to either input or output (default).

Input and output modules cannot be mixed within a group.

Up to eight optically isolated (500 V) digital input connec-

tion pairs are available from the signal I/O connector on

USB-PDISO8 Series devices.

Each signal is applied to a bridge rectifier so that the input is

not polarity-sensitive.

External Power

USB-PDISO8 Series devices require between 6.5 V and 12.5 V

of external power. USB-SSR Series and USB-ERB Series devices

require between 6.0 V and 12.5 V of external power.

An external power connection using the included external power

supply is required to activate relays and SSR modules, and to

run tests in software.

• USB-PDISO8 Series devices, USB-SSR Series devices, and the

USB-ERB08 are powered by a 9 V, 1.67 A external power

supply (CB-PWR-9) that ships with each device.

• The USB-ERB24 is powered by an external 9 V, 3 A regu-

lated power supply (CB-PWR-9V3A) that ships with the

device.

Daisy Chaining Multiple Devices

MCC high-voltage/relay DIO devices can be optionally daisy

chained to connect to the USB bus through the high-speed hub

on the host device. Up to four MCC USB devices can be daisy

chained to a single USB port on the PC using the standard/

included USB cables.

Make sure adequate power is provided to each connected device.

You can use an independent power supply for each device, or

connect a user-supplied custom cable to daisy chain power.

Voltage Drop

A drop in voltage occurs with each device connected in a daisy

chain configuration.The voltage drop between the power supply

input and the daisy chain output is 0.5 V maximum. Factor in

this voltage drop when configuringa daisy chain system to ensure

that at least 6.0 VDC is provided to the last device in the chain.

Supply Current

The following devices may require addition external power

adapters depending on the number of connected devices:

Device

External Power Consumption

(All Relays/SSR Modules On)

USB-PDISO8 Series

Draws 820 mA from the 1.67 A supply

USB-ERB08

Draws 750 mA from the 1.67 A supply

USB-ERB24

Draws 1.5 A from 3 A supply

USB-SSR24

Draws 800 mA from the 1.67 A supply

USB-SSR08

Draws 300 mA from the 1.67 A supply

Some devices may require their own external power supply in

a daisy chain configuration

If unsure as to how much current an application requires, MCC

recommends providing separate power to each connected device.