Transient Protection - Emerson Rosemount 8800D Series Reference Manual

Reference Manual
00809-0400-4004
6.3

Transient protection

The optional transient terminal block prevents damage to the flowmeter from transients
induced by lightning, welding, heavy electrical equipment, or switch gears. The transient
protection electronics are located in the terminal block.
IEEE C62.41 - 2002 Category B
The transient terminal block was verified using the following test waveforms specified in
the IEEE C62.41 - 2002 Category B standard:
• 3 kA crest (8 X 20 ms)
• 6 kV crest (1.2 X 50 ms)
• 6 kV/0.5 kA (0.5 ms, 100 kHz, ring wave)
6.3.1 Installing or replacing the transient protection
For flowmeters ordered with the transient protector option (T1), the protector is shipped
installed.
The transient protection kit includes the following:
• One transient protection terminal block assembly
• Three captive screws
When purchased separately from the transmitter, install the protector using a small
instrument screwdriver, a pliers, and the transient protection kit.
1. If the flowmeter is installed in a loop, secure the loop and disconnect power.
2. Remove the field terminal side flowmeter cover.
3. Remove the captive screws.
Reference Manual
Figure 6-3: 4–20 mA and pulse wiring with electronic totalizer/counter
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A. Power supply
B. Counter power supply
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Advanced installation
October 2021
R >250 Ω
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