Emerson Daniel 3818, Руководство по установке

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3.6.4 Digital input
The 3818 LNG Liquid Ultrasonic Flow Meter provides one digital input that can be used as a
general purpose input or used for synchronizing calibration (for flow calibration gating-
contact closure). The meter records the volume seen between switch closures. The
polarity of the input is configured as normal or inverted polarity.
• Polarity is determined by the IsDI1ForCalActiveLow and the gating edge is determined
by the IsDI1ForCalStateGated (calibrate edge gated or calibrate state gated).
• Calibration is started via an inactive>active state change and stopped via an
active
→
inactive state change.
The digital input must be configured via the Daniel MeterLink Tools
→
Edit/Compare
Configuration
page.
3.6.5 DHCP server switch settings
The meter can be configured to act as a DHCP server. The DHCP server is enabled/disabled
via CPU Module DHCP switch as follows:
Table 3-6: DHCP server switch settings
CPU Module switch DHCP server disabled DHCP server enabled
DHCP OFF ON
3.6.6 Configuration protect switch settings
The meter’s configuration parameters and firmware can be protected against changes via
CPU Module Write PROT. switch as follows:
Table 3-7: Configuration protect switch settings
CPU Module switch Configuration protected Configuration unprotected
WRITE PROT. ON (default) OFF
A complete list of write-protected parameters is in Appendix A .
3.6.7 External power source connection and fuse
Located inside the Transmitter Electronics Enclosure is a connector for a user-provided
external power source, a 2 Ampere fuse and a 24V loop power connection for ultrasonic
meter analog outputs, temperature or pressure transmitter devices. The current is limited
to 88mA.
Installation manual Electrical Installation
3-9000-771 May 2019
Installation manual 55