Schneider Electric LUFP7 user manual Diagnostic Only, Description of the error

5. Gateway Initialization and Diagnostics

The values of the EC and ED fields are described in the table below:

EC	Description of the error	ED	Notes
2#0000	Re-transmissions on the	Number of re-	Total number of re-transmissions carried out
	Modbus network	transmissions (1)	on the sub-network, for all slaves.
2#0001	A Modbus slave is missing	Address of the missing	—
		Modbus slave
2#0010	Several Modbus slaves	—	—
	are missing
2#0011	Excessive data in a	Address of the Modbus	This error occurs when the gateway receives too
	Modbus response	slave involved	much data in the response sent by one of its
			Modbus slaves.
2#0100	Unknown Modbus error	Address of the Modbus	—
		slave involved

(1)The re-transmission counter used to signal this error is not reset when the gateway generates this error code. If there are recurrent communication problems on the Modbus network, the gateway will generate this same diagnostic repeatedly, so as to tell the Profibus-DP master the total number of re-transmissions carried out as often as possible. This counter is reset when its value exceeds its maximum value (counter modulo 256: 16#FF Æ 16#00).

In the case of de-connection of one or several device on the Modbus sub-network, the LUFP7 gateway will first report re-transmission errors several times and then the error “A Modbus slave is missing” or “Several Modbus slaves are missing”. Later on when the LUFP7 will proceed to reconnection attempt, only the re-transmission error will be reported. Due to this, the indication of the errors error “A Modbus slave is missing” or “Several Modbus slaves are missing” may be perceived as very brief.

5.3. Diagnostic Only

The gateway uses a 16-bit register, located at the addresses 16#0000 and 16#0001 in its memory (inputs), to send diagnostics to the Profibus-DP master. A second 16-bit register, located at the addresses 16#0200 and 16#0201 (outputs), allows the Profibus-DP to acknowledge each of these diagnostics.

So you must configure your Profibus-DP master so that it has access to the first two bytes of the gateway’s output data area, as well as to the first two bytes of the gateway’s input data area (see chapter 4.2 Gateway Configuration under PL7 PRO and SyCon, page 26).

5.3.1. Gateway Status Word

The input word located at addresses 16#0000 (MSB) and 16#0001 (LSB) in the gateway’s input memory constitutes the gateway’s status word. Its structure is described below:

Bits Description

15ABC_HS_SEND: New gateway diagnostic

(See description of bit 15 of the Profibus-DP master command word, FB_HS_CONFIRM.)

14 Reserved.

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