User's Manual

Table Of Contents
Micropilot FMR67
76 V. 1, Rev. 3, 11-04-2017 Endress+Hauser
Overvoltage protection
Accessory Description
Overvoltage protection for
2-wire-devices
OVP10 (1 channel)
OVP20 (2 channel)
A0021734
Technical data
Resistance per channel: 2 * 0.5 Ω
max
Threshold DC voltage: 400 to 700 V
Threshold impulse voltage: < 800 V
Capacitance at 1 MHz: < 1.5 pF
Nominal arrest impulse voltage (8/20 μs): 10 kA
Suited for wire cross-sections: 0.2 to 2.5 mm
2
(24 to 14 AWG)
Ordering with device
The overvoltage protection module is preferably ordered with the device. See product structure, feature 610
"Accessory mounted", option NA "Overvoltage protection". Separate ordering of the module is only necessary if a
device is to retrofitted with the overvoltage protection.
Order code for retrofitting
For 1-channel devices (feature 020, option A)
OVP10: 71128617
For 2-channel devices (feature 020, option B, C, E or G)
OVP20 : 71128619
Hosuing lid for retrofitting
In order to keep the necessary safety distances, the housing lid needs to be replaced if the device is retrofitted with
the overvoltage protection. Depending on the housing type, the order code of the suitable lid is as follows:
GT18 housing: Lid 71185516
GT19 housing: Lid 71185518
GT20 housing: Lid 71185516
Restrictions for retrofitting
Depending on the approval of the transmitter the usage of the OVP module may be restricted. A device may only be
retrofitted with an OVP module if the option NA (overvoltage protection) is quoted unter Optional Specifications in
the Safety Instructions (XA) pertaining to the device.
For details refer to SD01090F.