Reference Manual
00809-0100-4004, Rev BA
August 2010
2-25
Rosemount 8800D
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.
The transient terminal block meets the following specifications:
IEEE C62.41 - 2002 Category B.
3 kA crest (8 X 20
s)
6 kV crest (1.2 X 50
s)
6 kV/0.5 kA (0.5
s, 100 kHz, ring wave)
NOTE
The ground screw inside the terminal housing must be tightened for the
proper operation of the transient protection. Also, a high-current ground
connection to earth is required.
Installing the
Transient Protector
For flowmeters ordered with the transient protector option (T1), the protector
is shipped installed. When purchased separately from the Rosemount 8800D,
you must install the protector on a Rosemount 8800D flowmeter using a small
instrument screwdriver, a pliers, and the transient protection kit (part number
8800-5106-3002 or 8800-5106-3004).
The transient protection kit includes the following:
• One transient protection terminal block assembly
• Three captive screws
Use the following steps to install the transient protector:
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.
4. Remove the housing ground screw.
5. Use pliers to pull the terminal block out of the housing.
6. Inspect the connector pins for straightness.
7. Place the new terminal block in position and carefully press it into
place. The terminal block may have to be moved back and forth to get
the connector pins started into the sockets.
8. Tighten the captive screws.
9. Install and tighten the ground screw.
10. Replace the cover.