E3A-JA3A-F11 Datasheet, PDF (6/60 Pages) Magnetrol International, Inc. – Liquid Level Displacer Transmitter

DDs are similar to the drivers that your personal computer
(PC) uses to operate peripheral devices connected to it. Any
Fieldbus host system can operate with a device if it has the
proper DD and Common File Format (CFF) for that device.
The most recent DD and CFF files can be found on the
FOUNDATION fieldbus^™ web site at fieldbus.org.
1.4 Intrinsic Safety
The H1 physical layer supports Intrinsic Safety (IS) applica-
tions with bus-powered devices. To accomplish this, an IS
barrier or galvanic isolator is placed between the power
supply in the safe area and the device in the hazardous area.
H1 also supports the Fieldbus Intrinsically Safe Concept
(FISCO) model which allows more field devices in a
network. The FISCO model considers the capacitance and
inductance of the wiring to be distributed along its entire
length. Therefore, the stored energy during a fault will be
less and more devices are permitted on a pair of wires.
Instead of the conservative entity model, which only allows
about 90 mA of current, the FISCO model allows a maxi-
mum of 110 mA for Class II C installations and 240 mA
for Class II B installations.
FISCO certifying agencies have limited the maximum
segment length to 1000 meters because the FISCO model
does not rely on standardized ignition curves.
The E3 Modulevel is available with entity IS, FISCO IS,
FNICO non-incendive, or explosion proof approvals.
1.5 Link Active Scheduler (LAS)
The default operating class of the E3 Modulevel with
FOUNDATION fieldbus^™ is a basic device. However, it is
capable of being a Link Active Scheduler (LAS). The LAS
controls all communication on a FOUNDATION fieldbus^™
segment. It maintains the “Live List” of all devices on a seg-
ment, coordinates both the cyclic and acyclic timing and, at
any given time, controls which device publishes data via
Compel Data (CD) and Pass Token (PT).
The primary LAS is usually maintained in the host system,
but in the event of a failure, all associated control can be
transferred to a backup LAS in a field device such as the
E3 Modulevel. The operating class of E3 Modulevel can be
changed from basic to LAS using a FOUNDATION fieldbus
configuration tool.
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48-640 E3 Modulevel Displacer Level Transmitter - FOUNDATION fieldbus^™