- Joined
- Jun 8, 2002
- Location
- Melbourne, Australia
Okay, just to keep all this info in a clearly labelled single thread:
The new Laing D4, which can be easily identified with its black, rather than blue, pump body, and a red 5-position speed dial on the back. Feedback from various water-cooling equipment retailers have informed that the pump will go by the MCP655 moniker from Swiftech in order to clearly designate the now quite different pump from the older Laing D4 (sold as the MCP650).
Some pictures of the new pump are here:
Back of pump
Closeup of speed-dial knob - shown in the #5 position
Isometric view of pump from front left
Isometric view of pump from front right
Just to avoid confusion, the pump label says:
Volts: 8-24
Watts: 3-33
Amps: 1.4
The pump is rated for up to 60C fluid temperatures, and a peak of 50PSI internal pressure. The 50PSI operation limit could only be reached in practise if a second pump was deployed before the D4's inlet providing >45PSI of pressure into the D4 pump, so this is not something to ever be concerned about for most everyone.
The big thing about the new D4 is the lack of noise. Anyone who's used one of the older D4's will know that they emit quite a loud and annoying buzz-like whine, some more loudly than others, but overall it's not a pleasant sound. These new D4's are now extremely quiet - quiet enough to challenge an Eheim 1250. This is not to say that the pump is silent, but it is quieter than almost any disk hard drive anyone cares to name that people put into their computers. Of course the pump does vibrate very slightly, and if it is allowed to vibrate or resonate against something then it can be quite noisy, but this is an issue that can be fairly easily solved by employing a small measure of vibration dampening.
Performance
I am still in the process of assessing the pump's performance characteristics, but I will say this in summary: it is significantly stronger at its highest speed setting (#5) than ANY prior Laing D4.
Right now all I have done are some peak pressure tests (how far vertically it will push a column of water), and the power draw under these conditions. My results are as follows:
12.0v input
Setting, Pressure, Power Draw
#5, 4.10mH2O, 21.0W
#4, 3.05mH2O, 14.5W
#3, 2.25mH2O, 11.0W
#2, 1.40mH2O, 7.0W
#1, 0.60mH2O, 4.0W
The speed dial on the back in actually a continuous type dial. Meaning it can be set inbetween whole values.
One very interesting observation was seen when attempting to over-volt the pump. I tried pushing up the voltage to 13.5v, and the peak dead-head pressure went to 4.2mH2O. I ramped it up to 16.0v and the peak pressure remained the same. I dropped the voltage down to 12.25v, and found that above this point that the peak pressure of 4.20mH2O did not change, and below this point is where it started to drop away. Dead-head power draw amperage remained constant as well for voltages between 12.25v and 16.0v, meaning that power draw was just ramping linearly with voltage above 12.25v.
Let me say all that again more clearly:
There is no point feeding the pump more than 12.25v, it simply will not go any faster.
I would imagine that this has been implemented within the pump's controller circuitry.
By the same token, decreasing the input voltage does not have a major effect on the pump's performance. Pressure does go down, but does not follow the same pattern as other pumps. With most other pumps the amperage drops off as the voltage is dropped, but not so with the new D4. Amperage remains the same and the pump remains pushing water to a vertical height of 2.5m even when just above its measured stall voltage of 7.5v. Below 7.5v, the pump just stops.
Again, there appears to be no point in either over- or under-volting the new D4. Just feed it 12v and adjust the speed on the knob on the back.
I will be conducting further tests to test for heat dump and generate some PQ flow curves. I'll be doing all these at 12v, since this is now obviously what the pump was designed for, and it's also the most relevent measurement point now given that most people will simply be running the pump off the 12v rail of their PSU.
The new Laing D4, which can be easily identified with its black, rather than blue, pump body, and a red 5-position speed dial on the back. Feedback from various water-cooling equipment retailers have informed that the pump will go by the MCP655 moniker from Swiftech in order to clearly designate the now quite different pump from the older Laing D4 (sold as the MCP650).
Some pictures of the new pump are here:
Back of pump
Closeup of speed-dial knob - shown in the #5 position
Isometric view of pump from front left
Isometric view of pump from front right
Just to avoid confusion, the pump label says:
Volts: 8-24
Watts: 3-33
Amps: 1.4
The pump is rated for up to 60C fluid temperatures, and a peak of 50PSI internal pressure. The 50PSI operation limit could only be reached in practise if a second pump was deployed before the D4's inlet providing >45PSI of pressure into the D4 pump, so this is not something to ever be concerned about for most everyone.
The big thing about the new D4 is the lack of noise. Anyone who's used one of the older D4's will know that they emit quite a loud and annoying buzz-like whine, some more loudly than others, but overall it's not a pleasant sound. These new D4's are now extremely quiet - quiet enough to challenge an Eheim 1250. This is not to say that the pump is silent, but it is quieter than almost any disk hard drive anyone cares to name that people put into their computers. Of course the pump does vibrate very slightly, and if it is allowed to vibrate or resonate against something then it can be quite noisy, but this is an issue that can be fairly easily solved by employing a small measure of vibration dampening.
Performance
I am still in the process of assessing the pump's performance characteristics, but I will say this in summary: it is significantly stronger at its highest speed setting (#5) than ANY prior Laing D4.
Right now all I have done are some peak pressure tests (how far vertically it will push a column of water), and the power draw under these conditions. My results are as follows:
12.0v input
Setting, Pressure, Power Draw
#5, 4.10mH2O, 21.0W
#4, 3.05mH2O, 14.5W
#3, 2.25mH2O, 11.0W
#2, 1.40mH2O, 7.0W
#1, 0.60mH2O, 4.0W
The speed dial on the back in actually a continuous type dial. Meaning it can be set inbetween whole values.
One very interesting observation was seen when attempting to over-volt the pump. I tried pushing up the voltage to 13.5v, and the peak dead-head pressure went to 4.2mH2O. I ramped it up to 16.0v and the peak pressure remained the same. I dropped the voltage down to 12.25v, and found that above this point that the peak pressure of 4.20mH2O did not change, and below this point is where it started to drop away. Dead-head power draw amperage remained constant as well for voltages between 12.25v and 16.0v, meaning that power draw was just ramping linearly with voltage above 12.25v.
Let me say all that again more clearly:
There is no point feeding the pump more than 12.25v, it simply will not go any faster.
I would imagine that this has been implemented within the pump's controller circuitry.
By the same token, decreasing the input voltage does not have a major effect on the pump's performance. Pressure does go down, but does not follow the same pattern as other pumps. With most other pumps the amperage drops off as the voltage is dropped, but not so with the new D4. Amperage remains the same and the pump remains pushing water to a vertical height of 2.5m even when just above its measured stall voltage of 7.5v. Below 7.5v, the pump just stops.
Again, there appears to be no point in either over- or under-volting the new D4. Just feed it 12v and adjust the speed on the knob on the back.
I will be conducting further tests to test for heat dump and generate some PQ flow curves. I'll be doing all these at 12v, since this is now obviously what the pump was designed for, and it's also the most relevent measurement point now given that most people will simply be running the pump off the 12v rail of their PSU.