Schneider Electric Processor Adapter manual Scantime Formula for 984LL Exec Example

Overview of Momentum M1 Processor Adapters

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Specifications,

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Storage Conditions

Temperature	-40 ... +85 degrees C
Humidity	5 ... 95% (noncondensing)
Safety Parameters
Degree of protection	Unintentional access (UL 508 Type 1, NEMA250 Type 1,
	IP20 conforming to IEC529)
Di-electric strength	Ethernet is isolated from logic common 500 VDC
Ground continuity	30 A test on the exposed metal connector
Agency Approvals	lUL 508, CSA, CUL, CE
	FM class1, div2

Scantime Formula for 984LL Exec

Example

The following formula applies to the M1E Processor Adapter with the 984LL exec.

Scan time = (0.25 msec/ethernet device + 0.002 msec/word) + 0.13 msec/K of logic + 0.40 msec + MBPlustime

Note:

Modbus Plus communications will slow the M1E. If there is no MB+ ring card then MBPlustime = 0.

If there is a MB+ ring card, then each scan will be extended 0.3 Msec even if there is no message.

Modbus Messages will add from 1 to 2 msec per scan, depending on the length of the message.

Note:

The formula above presumes that all MSTR blocks and all configured connections are set to go as fast as possible. In this case the M1E will attempt to exchange data with

leach device once per scan.

If several devices are configured to communicate on a timed basis that is substantially larger than the scan time calculated, then the communications to those devices will be spread out over several scans. See Example, below.

You have 50 ENT modules connected to a single M1E with a configured time of 50 Msec each, a total of 4k user logic and no MB+ card. The scan time for all modules configured as fast as possible would be 12.5 Msec + 0.52 Msec + 0.40 Msec =

13.42Msec. However, since the M1E will only communicate to 1/4 of the modules

(12.5 Msec/50 Msec = 1/4) on any given scan, the corrected average scan time would be 1/4 x (12.5) + 0.52 + 0.40 ≅ 4.1 Msec.

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