Voltage / Current Monitor - SFVCM

The SFVCM (Shaft Fault Voltage Current Monitor) prevents costly machine parts replacement by detecting when damage is caused by shaft currents. Frosting, pitting and spark tracking are just the start of problems that shaft currents can create. The SFVCM is installed into the shaft grounding brush cable allowing you to read and trend the peak shaft voltage and grounding brush current. With this information you can predict the onset of problems earlier than ever before. The SFVCM will detect problems before they show up in vibration or temperature readings because the shaft current and voltage profiles are affected first. Once you see the value of shaft voltage and current readings, you'll agree that the SFVCM is an essential component of any new or existing shaft grounding system.

Non-Ex-Proof (single)


Non-Ex-Proof (double)




Key features 

- Turn any shaft grounding brush into a valuable predictive maintenance tool.

- Data to assist in trending peak shaft voltage, peak brush current and average brush current.
- Find out if your brush is grounding properly
- Make it safer to disconnect your brushes in a hazardous environment.
- Attach it to any insulated shaft riding brush.

Technical data 


3 digit liquid crystal display indicating Peak or Average Current or Peak Shaft Voltage or Power/Alarm Check, selected with rotary switch

Analog output

4 to 20 mA signal representative of Peak Ground (Earth) Current

4 to 20 mA signal representative of Average Ground (Earth) Current

4 to 20 mA signal representative of Peak Shaft Voltage

Local alarm

LED for minimum and maximum brush current and maximum shaft voltage

Remote alarm

Open contact on minimum and maximum current, maximum shaft voltage and loss of power supply to the unit * (User selectable latching is optionally available in Non-Explosion-Proof Enclosures Only)


Ground (Earth) Current Lead (from shunt in ground (earth) circuit), Voltage Lead (from shaft-monitoring, voltage sensing brush)

Power supply

115 - 240 Vac, 50/60 Hz to power supply module, to be mounted by user.


Operating temp. -10 0C to 50 0C (14 0F to 122 0F), storage temp. -23 0C to 60 0C (-10 0F to 140 0F)


100 mV shunt for 1, 2, 5, 10, 20, 50, 100, or 200 A (SFVCMS supplied).

Relative Humidity

0% to 95%, non-condensing


Non-Ex-Proof (single)

Non-Ex-Proof (dual) Ex-Proof


5.00 in (127 mm)

4.65 in (118 mm) 7.60 in (193 mm)


7.31 in (185.7 mm)

11.81 in (300 mm)       7.60 in (193 mm)


7.31 in (185.7 mm)

10.25 in (260 mm) 7.80 in (198 mm)


3.0 lbs (1.36 kg)

7.5 lbs (3.4 kg) 15 lbs (6.8 kg)


Type A


Type L


Type LW