Q. What PLCs can the GembusHub be used with?

Any device  that supports Modbus.
This does not have to be a PLC the GembusHub is intended to interface to external PLC/DCS devices using Modbus TCP/IP. It is also possible to use any of the Gembus ports as a serial connection port for a controlling device. This would allow a PLC to connect to the GembusHub using Modbus RTU.
All of the control and monitoring functions available using either method of connection.

We have it running with Siemens S7 1200, Modicon M340 and Fanuc Rx3i PLCs.

Q. How many PLC or DCS systems can connect to a single GembusHub?

The Modbus interface allows for a maximum of 16 Modbus clients to connect at any time. This would allow different client devices  to control specific Gemstart links on a common GembusHub.

Additionally each of the 4 wire RS485 ports normally used to host Gemstart units can be configured to allow PLC Modbus RTU access. These then become Modbus RTU RS845 4 wire links.

Q. How are the various parameters for each link specified?

All of the parameters required are published in the Modbus data map. This allows any attached client device to change the values. So the program in a DCS or PLC can provide routines to set the GembusHub parameters as required.
Alternatively a utility has been produced which also allows the various parameters to be set. This can be downloaded from the support page.

Q. Can Apstar do the Engineering supply and build any panels that may be required?

Yes Apstar have a long history of suppling PLC systems to be used with Motor controllers. Please contact us for a quotation.

Q. Can any device that can gain access to the network communicate to the TCP/IP port of the GembusHub?

For security, the GembusHub can restrict client access to ranges of IP addresses. There are 16 user selectable ranges of IP addresses. If used any client trying to connect must have an address that is within one of the selectable ranges.

Q. After changing settings do I need to power cycle the GembusHub?

This is only required when some of the IP Address related settings are changed. In this case the GembusHub sets a status bit to indicate that a reset is required. This can be done by physically turning the power off nd on, or by issuing a command by a client using a Modbus message.
If the GembusHubView is connected then this can be used to send a restart message.

Q. We have a GE Fanuc 90-30 and 90-70 which we need to upgrade can this unit replicate all of the PCM functionality?

Yes all of the PCM capabilities are present in the GembusHub. It is also worth remembering that it provides 4 Gemstart links not just 2 as the PCM does.

Q. This unit looks great, but I would like it to have a different protocol, in place of, or as well as Modbus. Is this possible?

• That could be done if:
• The full details of the required protocol are available. We would need all of the technical detail to implement the protocol in code.
• You or your client are willing to fund the development work. We would be happy to provide a quotation, please contact us if this is of interest.