SubDrive/MonoDrive | Franklin Water

What does it mean if my SubDrive/MonoDrive Connect is displaying F1?

If the SubDrive/MonoDrive Connect displays F1, it signals a motor underload fault. The motor is drawing less current (amperage) than the minimum parameter setting.

Possible Causes	Corrective Actions
Damaged pump	Repair or replace pump and motor assembly as needed.
Plugged screen	Remove debris from pump screen.
Invalid DIP switch selection for pump end HP (on new installs)	Verify DIP switches are set properly.
System is drawing down to pump inlet (out of water); over-pumped well; well is running dry	If not out of water, check the underload sensitivity setting.
High static, light loading pump
Frequency near maximum, with load less than configured underload sensitivity
Incorrect/backwards motor rotation	Check pump rotation (SubDrive and three-phase motor only). Reconnect if necessary for proper rotation.
Air/gas locked pump	If possible, set deeper in well to reduce possibility of air/ gas locked pump.
Maximum frequency set too low for permanent magnet motor	For MagForce™ motor, increase maximum frequency to 125Hz or more for - if maximum frequency must be below 125Hz, adjust underload sensitivity setting to a lower value.

What does it mean if my SubDrive/MonoDrive Connect is displaying F2?

If the SubDrive/MonoDrive Connect displays F2, it signals an undervoltage fault. The voltage provided to the drive unit is measured to be less than 180 VAC. The measurement is between the L1 and L2 terminals at the incoming power connection terminals.

Possible Causes	Corrective Actions
Low incoming voltage measured at the drive terminals	The line voltage needs to be 190 to 260 VAC. Correct incoming voltage. Contact the power company.
Mis-wired input leads	Check incoming power connections and correct or tighten if necessary.
Loose connection at breaker or panel	Check circuit breaker or fuses.
Possible internal drive issue	If above measurements and corrections are made with no resolution, replace drive.

NOTE: Refer to the owner’s manual for more information.

What does it mean if my SubDrive/MonoDrive Connect is displaying F3?

If the SubDrive/MonoDrive Connect displays F3, it signals an overcurrent or locked pump fault. If the motor current is higher than the maximum load or service factor amperage of the motor, then the drive tries to lower the speed to bring the current below the limit while lowering the speed below a certain frequency. If the overcurrent is still active, the drive declares F3.

Possible Causes	Corrective Actions
Motor and/or pump misalignment	Remove and repair or replace as required
Dragging motor and/or pump
Motor and/or pump locked
Abrasives in pump
Open phase on 3 wire motor with long leads
Excess motor cable length	Reduce motor cable length. Adhere to Maximum Motor Cable Length table in the owner’s manual.
Amperage above motor maximum load or service factor level at 30 Hz	Confirm correct setting for pump and motor and inspect pump for motor for mechanical interference.
Incorrect motor selection during drive DIP switch programming.	Confirm the motor type on DIP SW1 Position 7 is set correctly. Confirm the motor HP on DIP SW2 Positions 1-6.

NOTE: Refer to the owner’s manual for more information.

What does it mean if my SubDrive/MonoDrive Connect is displaying F5?

If the SubDrive/MonoDrive Connect displays F5, it signals an output open phase fault. The drive is seeing little or no current on one or more motor leads. If no current or low current is detected in one of the motor phases, then F5 will be declared.

Possible Causes	Corrective Actions
Loose connection anywhere in the motor cable or directly to the drive	· Check the drop cable and motor resistance, tighten output connections, and repair or replace as necessary. · Use dry motor to check drive functions. If drive runs and exhibits an underload fault, drive is good. · Perform a megger test at the motor lead on the drive end. · IMPORTANT: Make sure to disconnect the lead from the VFD before testing.
Defective motor or drop cable (disconnected cable)
Motor phase and horsepower do not match the drive settings.	· Confirm the motor phase DIP SW1 Position 2, and motor HP on DIP SW2. · Confirm motor settings match the motor being used.

NOTE: Refer to the owner’s manual for more information.

What does it mean if my SubDrive/MonoDrive Connect is displaying F6?

If the SubDrive/MonoDrive Connect displays F6, it signals a short circuit fault. Any short between the motor leads is detected as an F6 fault.

Possible Causes

Corrective Actions

Phase to phase short

· Check the drop cable and motor resistance. Perform a megger test at the motor leads on the drive end. IMPORTANT: Make sure to disconnect the lead from the VFD before testing.

· Fix wiring as necessary. If fault is present after resetting and removing motor leads, replace the drive.

Phase to ground short

NOTE: Refer to the owner’s manual for more information.

What does it mean if my SubDrive/MonoDrive Connect is displaying F27?

If the SubDrive/MonoDrive Connect displays F27, it signals a pressure transducer error. The 4-20 mA signal received from transducer is not within range.

Possible Causes	Corrective Actions
Pressure transducer has failed	Replace pressure transducer
Pressure transducer is incorrectly wired	Check pressure transducer wiring connections
Pressure transducer is in use but the DIP switch selection for the type of sensor input is incorrect	Ensure DIP SW1 Position 5 is in the correct position for the sensor type being used: DOWN for pressure transducer, UP for pressure switch.

NOTE: Refer to the owner’s manual for more information.

What is the difference between a pressure sensor and transducer?

A pressure sensor (Hobbs Switch) opens or closes a circuit depending on whether the actual pressure is above or below the desired pressure. Franklin Electric supplies pressure sensors that are factory set to 50 PSI and are NC (normally closed) contacts.

A pressure transducer sends a variable milliamp (mA) signal to the drive proportional to the water pressure detected. Franklin Electric has used two different versions of a pressure transducer. The transducer versions are compatible with all SubDrive products that accept a pressure transducer, regardless of age.

For more information, watch this 30-second video or this 2-minute video about the difference between transducers and pressure sensors.

Why does the pressure transducer for my SubDrive/MonoDrive Connect have plastic bushing at the end of it?

The plastic bushing on the pressure transducer on the SubDrive/MonoDrive Connect is an isolator. It was added after Franklin Electric upgraded the part for several SubDrive products to provide improved surge performance.

The configuration of a Franklin Electric transducer is slightly different from other suppliers. If purchasing a transducer from another supplier, keep the following in mind:

Same wire connection type (Packard Metri-Pack 150)
Same plumbing fitting and connection type (1/4” NPT)
Similar overall dimensions

NOTE: The Sensata + Isolator pressure transducer solution has been the standard offering with SubDrive Utility “XD” models since product launch (September 2021)

Why should I use a transducer or pressure sensor with my SubDrive constant pressure controller?

When using the transducer, the SubDrive Constant pressure controller allows for more programming functions:

Function	Transducer	Pressure Sensor
Voltage (VDC)	24	Pulsed signal
Pressure Measurement (psi)	Up to 200*	Up to 150**
Max distance from SubDrive (ft)	200	100
Drawdown	Yes	No
Overpressure Setpoint
Proportional Gain
Integration Time
Bump Mode	Pressure Bump Level, Bump Timeout, Delay to Sleep	Off, Standard, Aggressive Large Tank/Small Tank
Pressure Adjustment Location	At SubDrive unit	At Sensor
Pressure Adjustable through FE Connect App	Yes	No

NOTE: *SubDrive Connect models come with a 100 psi transducer. Franklin Electric offers accessories for up to 200 psi.

NOTE: **SubDrive Connect models do not come standard with the pressure sensor. Franklin Electric offers two kits with a pressure sensor. One kit has a max rating of 90 psi, and the other has a max rating of 150 psi.

Do the SubDrive products include electrical noise filtering? My old SubDrive affected my AM radio.

Yes, the current SubDrive Connect design includes enhanced electrical noise filtering. Read more in this news article and/or in this technical bulletin.

What are the environmental constraints regarding SubDrive Connect installation locations?

The SubDrive Connect is suitable for outdoor use with a NEMA 3R rating; however, the following considerations should be made for outdoor installations:

Mount the drive on a wall or back plate that is at least 6 inches (15.24 cm) larger than the outer dimensions of the enclosure to maintain the NEMA 3R rating.
Mount the unit vertically with the wiring end oriented downward and properly secure the cover (also applies to indoor installations).
Protect the unit from hose-directed or sprayed water as well as blowing rain. NEMA 3R enclosures can withstand downward-directed rain only. Failure to do so may result in SubDrive failure.
Install the unit away from direct sunlight or locations subject to extreme temperatures or humidity.
Clean screens on a regular basis to ensure proper airflow.
Use appropriate cord grips and strain relief to ensure all openings are sealed.

NOTE: Refer to the owner’s manual for more information.

Can I replace the display in my SubDrive Connect unit?

Yes, the display is a replaceable item. You will need to know the serial number or date code to confirm correct replacement part. Click here for a complete list of available parts.

Do you offer a lightning protection device for my SubDrive unit?

Yes, Franklin Electric has a surge arrestor to protect against lightning: part number 150814902.

Will the Franklin Electric SubDrive Connect work with non-Franklin pumps and motors?

Franklin Electric has optimized the SubDrive Connect Variable Frequency Drive for use with all Franklin Electric products. Using the Franklin Electric SubDrive with non-Franklin Electric products may result in suboptimal performance.

Is there a way to clear faults that are being shown on the SubDrive Connect display?

All faults are recorded in a log file for review during troubleshooting activities. Some faults may be temporary, allowing the drive to restart after a timeout period. However, certain faults can cause the SubDrive to cease operation of the pump and motor. In such cases, the SubDrive can be powered off, and after a few minutes, powered back on. The SubDrive will attempt to restart the pump and motor, but the initial fault condition may cause the unit to return to a ceased operation state. If this happens, further troubleshooting specific to the fault code being shown may be required.

Can the SubDrive Connect be reset to factory default?

Yes. A factory reset can be completed through the FE Connect App or manually on the drive. To reset manually on the drive:

Power down the SubDrive Connect unit.
Wait for the display to go blank and the unit to show no other light indications.
Remove the cover.
Record DIP switch positions as seen on all three DIP switch banks.
- Banks are identified as SW1, SW2, and SW3.
Place all DIP switch positions to down or off.
Replace the cover.
Power up the SubDrive Connect unit.
- The LCD display should show F24.
- F24 indicates the required settings are invalid. This is an acceptable result to reset the SubDrive unit.
Power down the unit.
Wait for the display to go blank and the unit to show no other light indications.
Remove the cover.
Complete the DIP switch changes for the required pump and motor assembly.
Replace the cover.
Power up the SubDrive unit.

Should I update the SubDrive firmware?

Consult your Franklin Electric water well professional for advice on firmware updates. Refer to the Firmware Release Notes.

What are the soft start features of the SubDrive Connect and SubDrive/MonoDrive NEMA 4?

When the SubDrive/MonoDrive Connect NEMA 4 detects that water is being used, the drive starts and increases the motor speed slowly, gradually increasing voltage, resulting in a cooler motor and lower start-up current compared to conventional water systems.

NOTE: Two-wire motors do not have soft start ability.

My inspector says the SubDrive Connect unit must be on a Ground-Fault Circuit Interrupter (GFCI) or an Arc-Fault Circuit Interrupter (AFCI). How do I install the SubDrive Connect unit to be compliant with the inspector's requirements?

Follow local codes and standards. Franklin Electric does not recommend using a Ground Fault Circuit Interrupter (GFCI) and/or an Arc-Fault Circuit Interrupter (AFCI). Use of a GFCI and/or an AFCI may cause nuisance trips.