Bullet VFD Technical FAQ

1~13   About Product 

14~28 About Installation 

29~34 About Operation 

35~41 About Service 

 

 About Product:

  1. How much water pressure the INVERTER can withstand?

The INVERTER can withstand up to 10bar(145psi) system pressure.

 

  1. What is the dB range of the INVERTER?

The INVERTER has a water-cooled design, and basically, it doesn’t produce any noise. Compare to any fan-cooled VFD, the INVERTER is much quieter.

 

  1. What size of water pumps that the INVERTER can work with?

The INVERTER has 2 models. BV1-11 can withstand 1.1kW (P2), while BV1-15 can withstand 1.5kW (P2).

 

  1. What types of water pump that the INVERTER can work with?

The INVERTER can work with many types of water pump such as horizontal &vertical multistage centrifugal pump, single-stage centrifugal pump, self-priming peripheral pump, self-priming jet pump, deep well submersible bore pump, and many more.

 

  1. What is the highest temperature of water and ambient that the INVERTER can withstand?

The INVERTER can withstand up to 50°C water and 50°C ambient.

 

  1. Can I upgrade my existing pump with the INVERTER?

So far, The INVERTER can only work with 3phase 220-240V water pumps, but not with 1phase water pumps.

 

  1. Will the pump stop running when the INVERTER detects a leaking problem?

When the INVERTER detects a leakage problem, red-light #4 will be flashing, but it can still operate normally.

 

  1. Can I replace the standard pressure tank with a bigger one?

Yes, you can always replace it with a larger pressure tank (up to 8 liters for direct-connection or unlimited-size for indirect-connection.) However, because the INVERTER has a soft start and soft stop function, the size of the pressure tank does not have to be large.

 

  1. How much pressure should be charged in the pressure tank?

The pressure charging of the pressure tank should base on the pressure Set-Point of the INVERTER. Otherwise, the INVERTER will operate abnormally. Below shows the recommended pressure charging compare to the Set-Point:

Pressure Charging

Set-Point

3.3bar (45psi)

6.0bar (84psi)

3.0bar (41psi)

5.5bar (77psi)

2.7bar (37psi)

5.0bar (70psi)

2.4bar (33psi)

4.5bar (63psi)

2.1bar (29psi)

4.0bar (56psi)

1.8bar (25psi)

3.5bar (49psi)

1.5bar (21psi)

3.0bar (42psi)

1.2bar (17psi)

2.5bar (35psi)

0.9bar (13psi)

2.0bar (28psi)

0.6bar (9psi)

1.5bar (21psi)

0.3bar (5psi)

1.0bar (14psi)

 

 

          10. How does this INVERTER save energy?

Using VFD to save energy is based on two main factors：

a. When the water consumption does not require the pump to run at full speed, the VFD will reduce the pump speed and then reduce the power consumption.

b. When using a three-phase pump with a VFD, the efficiency of a three-phase motor is higher than that of a single-phase motor, so energy can be saved. By using a VFD, you can use a single-phase power supply to run a three-phase motor.

 

           11. How does this INVERTER dissipate heat?

The INVERTER has a water-cooled design. With this special design, the water flow through the flow channel could reduce the temperature of the IGBT, so that the INVERTER can operate normally and extend its service life.
Compared with the traditional air-cooled design, the water-cooled design has a quieter running sound and saves space.

 

           12. What is absorbed current? And why it is higher than the pump current?

Absorbed current refers to the false current value generated by virtual work. Since this INVERTER has no PFC function, the current in the meter is not the actual power consumed. If you want to know the actual power consumption, please use a digital multimeter to check the actual current at the incoming electricity wire.

 

          13. Can this INVERTER be used to assemble a dual pump system?

This INVERTER does not have the built-in functions of a dual pump system; however, you can still use a PLC, timer, and additional pressure sensor to assemble a dual pump system.

 

About Installation:

           14. Can the INVERTER be installed outdoors?

Yes, the INVERTER has IP55 protection grade and can be installed in outdoor environments exposed to direct sunlight and rain. However, it is best to have protection cover for the inverter pump system.

 

           15. Do I need to install a pressure tank for the INVERTER pump system?

The INVERTER already contains a rechargeable 0.6L (0.16 gallon) SS304 pressure tank, so there is no need to install another pressure tank.

 

           16. Do I need to install a pressure gauge for the INVERTER pump system?

The INVERTER will indicate the actual system pressure on the dashboard, so there is no need to install a pressure gauge for the INVERTER pump system.

 

           17. Do I need to install any check valve for the INVERTER pump system?

The INVERTER already has a built-in check valve to prevent water from flowing back into the pump, water hammer damage, and to maintain the pressure in the pressure tank. However, it is still necessary to install a check valve before the pump inlet to prevent the water backflow from the pump to the water source and to ensure that the INVERTER pump system has a suction lift capacity.

 

           18. Do I need to install any ball valve for the INVERTER pump system?

Yes, it is best to install a ball valve before the inlet check valve of the pump and install another one after the outlet of the INVERTER to facilitate future maintenance.

 

           19. Do I need to install a protective circuit breaker for the INVERTER?

Yes, for safety reasons, and especially for electrical leakage protection, it is necessary to install an appropriately sized protective circuit breaker according to the rated current of the INVERTER pump system.

           

           20. Do I need to install a pressure reducing valve before the INVERTER pump system?

The outlet pressure of the INVERTER pump system is constant, which is different from ordinary fixed-speed booster pumps. A fixed-speed booster pumps will increase pressure on the top of the incoming pressure and may cause the excessive system pressure, which may lead to pipeline damage and water leakage. However, it is best to install a pressure relief valve after the INVERTER pump system to prevent overpressure caused by a failure of the pressure sensor.

 

           21. Do I need to install a pre-filter for the INVERTER pump system?

In the case of general clean water, there is no need to install a pre-filter. However, if water sources such as well water or river water are not completely clean, a pre-filter must be installed.

 

           22. Do I need to prime the water pump?

Yes, the water pump must be primed to exhaust air for smooth water transfer and avoid cavitation damage.

 

           23. Do I need to prime the INVERTER when installing it?

In the case of a positive pressure water supply, the INVERTER does not need to be primed. But in the case of a negative pressure water supply, it is necessary to prime the INVERTER to prevent overheating shutdown or product damage.

 

           24. What direction that the INVERTER can be installed?

The INVERTER can work in multiple directions such as vertically face-front, and horizontally face-front, face-up, and face-down for flexible installation and pipeworks. In addition, when installed horizontally, you can also rotate the panel for easier reading.

 

           25.How do I connect the wire of the INVERTER with the pump?

You can connect the wire and earth with the pump cable directly or with the terminal board of the motor. However, please note that misconnecting would cause the wrong direction of the rotor turning. Below is the wire comparison chart for your reference.

U

Brown

L1

A

V

Black

L2

B

W

Grey

L3

C

 

 

           26. How do I check if the motor is rotating in the right direction or not?

You can observe from the motor fan cover hole. If the motor rotates in the correct direction, the fan should rotate according to the direction-indicating sticker.

 

           27. What happens if I connect the wrong power cord?

The INVERTER has two cables, one is used to connect the power supply, and the other is used to connect the pump motor.

The power cable contains three wires, two of which are used to connect to the power source and the other is used to ground. It doesn't matter how the two wires are connected, there is no wrong connection, but remember not to connect the ground wire to the power supply, otherwise, the inverter will be damaged.

 The cable connected to the water pump motor includes four wires, among which brown, black, and gray are used to connect to the U, V, W, or L1, L2, and L3 marked on the terminal block. If they are connected incorrectly, the motor rotation will reverse, but please remember not to connect the ground wire to the part of the electricity on the terminal block, otherwise, the inverter will be damaged.

 

           28. What specifications of leakage protectors should be used for this                         INVERTER?

10mA leakage circuit breaker is suitable for both model BV1-11 and BV1-15.

 

About Operation: 

           29. How do I adjust the set pressure?

First, if the LOCK light is on press the UNLOCK button, and then press the UP or the DOWN button to adjust the set pressure base on your need.

 

           30. When can I adjust the set pressure?

You can adjust the set pressure anytime when the power is on. However, please make sure not to exceed the maximum-producing pressure of the pump.

 

           31. What should I do when the self-priming process is too long and trigger the INVERTER into dry-running protection mode?

You can long-press the START button for forced operation or press the RESET button to release the dry-running protection mode until the self-priming is completed. However, before you do it, please make sure the INVERTER is fully primed. 

 

           32. Do I need to unplug the INVERTER when I’m not using it?

To provide the pump with locked-rotor protection and anti-freeze protection, please do not unplug the INVERTER even if it is not used for a long time.

 

           33. What does the blue light mean?

  • Scrolling blue light: the INVERTER pump system is in operation mode.
  • Firmed blue light: the INVERTER pump system is in standby mode.
  • Flashing blue light: the INVERTER pump system is in paused mode.
  • The highest blue lighted number is the actual system pressure.

 

           34. Does the INVERTER need to be adjusted when it is used in deep well submersible pumps?

Yes, if you want to use it in deep well pumps, please open the panel cover and switch the S101 switch to UP. In this way, the carrier frequency will be adjusted to 2K which is more suitable for deep well pumping.

 

About Service:

           35. What does the red light mean?

If the dashboard shows a red light, it indicates a problem with the pump, the power supply, the water supply, the environment, or the INVERTER itself. Please follow the table below to understand the situations and related remedies. Please note that a flashing red light is a warning, and the pump can still operate, but a firmed red light will stop the pump.

Identifier

Description

Remedy

0

Overvoltage or low voltage

Check if the incoming voltage to the INVERTER is too high or too low

 1

 

Over current

Check whether the maximum current of the selected motor exceeds the  acceptable range

Blocked rotor

Check if the impeller and fan are stuck

Phase failure

Check whether the motor wiring is correct

Motor disconnected

2

 

 

Excess temperature

 

 

The INVERTER will restart after cooling down. If it doesn’t, please check whether the temperature of the water or the environment exceeds the acceptable range.

3

 

 

Dry running

Check the water source

Check if the priming is complete

Check whether the pipeline and pre-filter are closed, blocked or leaked

 

Pressure set point is too high

Reduce the set pressure or choose a suitable pump

Check if the motor runs in correct direction

4

Leakage warning

Check for leaks in the pipeline or other water-using equipment

Pressure tank losing pressure

Check if the pressure tank lose pressure or has damage

5

 

System pressure is too high

Check if the incoming water pressure is too high

Check if the set pressure is too high

Abnormal pressure sensor

Check whether the pressure sensor and its connection is normal

6

Abnormal flow switch 

Check if the flow switch is stuck

Check if the flow switch is damaged

Abnormal inverter board

Try to replug the INVERTER    

 

 

           36. What should I do after following the recommended remedy and solve the problem?

After solving the problem, if the pump does not operate normally, please press the UNLOCK button first, and then press the RESET button. After completing these steps, the operation should return to normal.

 

           37. How to check whether the pressure sensor is normal or not?

First, turn off the water source, drain the water in the pipe, and turn off the power. And then, remove the pressure sensor cover, remove and reinsert the pressure sensor connector, turn on the water supply, prime the pump, turn on the power, and check if the operation returns to normal.

If the first method does not work, please again turn off the water source, drain the water in the pipe, turn off the power, and remove the connector. And then, use a screwdriver to remove the four screws, remove the pressure sensor, and check if there is any foreign object stuck in it. After ensuring that the interior is clean, put the pressure sensor and the o-ring back in place, tighten the four screws, reinsert the connector, turn on the water supply, prime the pump, turn on the power, and then check whether the operation can return to normal.

If the second method does not work, replace the pressure sensor with a new one.

To ensure that the pressure sensor can detect the correct pressure, please use a pressure gauge to measure the system pressure, and check whether the number is the same as the one indicated on the INVERTER dashboard. Please note that the measuring position of the pressure gauge should be close to the INVERTER.

 

           38. How to check whether the flow switch is normal or not?

First, turn off the water source, drain the water in the pipe, turn off the power, then use a wrench to remove the flow switch cover, and then remove the spring and flow switch. And then, check the flow switch, spring, or flow switch chamber for foreign objects stuck. After making sure everything is clean, put the flow switch and spring back in place, attach the o-ring on the cover, tighten the cover, then turn on the water supply, prime the pump, and turn on the power to check if the operation can return to normal.

If the first method does not work, replace the flow switch with a new one. However, if it still doesn’t work, the inverter board might be damage.

 

           39. How to recharge the pressure tank?

First, drain the water in the pipeline and ensure there is no any system pressure within. Then use an Inflator to recharge the pressure tank.

 

           40. What should I do after following the recommended remedy and still could not solve the problem?

If your problem can not be solved by the recommended remedy, please contact your INVERTER supplier for further assistance.

 

           41. What should I do if an airlock occurs at the water inlet end of the inverter?

You can open the flow switch cover on the top of the INVERTER, take out the spring and the check valve inside, and inject water from the hole until the water is full, and the air is discharged. Then put the check valve and spring back, and lock the cover back.