Schneider Electric Processor Adapter - Manual (Page 50)

Overview of Momentum M1 Processor Adapters
50 870 USE 101 10 V.2
171 CCC 960 20, Continued
Specifications,
Continued
Scantime
Formula for
984LL Exec 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
Example 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 =
13.42 Msec. 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.
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 l UL 508, CSA, CUL, CE
l FM class1, div2
Note:
l Modbus Plus communications will slow the M1E. If there is no MB+ ring card then
MBPlustime = 0.
l If there is a MB+ ring card, then each scan will be extended 0.3 Msec even if there is no
message.
l Modbus Messages will add from 1 to 2 msec per scan, depending on the length of the
message.
Note:
l 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
each device once per scan.
l 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.