Pro/Forums - View Single Post - Common pump P-Q Curves (graph inside)

Cathar · 01-17-2004, 09:54 PM

Posted this at OCAU.

Some notes:

*) This post was designed for an Australian audience. Ignore the prices listed unless you want a good laugh about how much us Aussies get ripped off on pump pricing.

*) The Danner Mag 3 line is my personal interpretation of a best fit line given the data presented at their website. Their data produces a line that is not even remotely smooth, so I look the liberty to smooth it out somewhat. If anything, I may have overestimated slightly. The in-line heat figure is another approximation drawn from reading about people's experiences. I believe it to be somewhat close.

*) The Swiftech MCP600 in-line heat is another approximation, based on motive pumping power which must be ultimately converted as frictional heat into the water, and some heat from the motor itself.

*) The Johnson pump may be obtained for the price stated from www.depcopump.com. The in-line heat value is an approximation based on my experiences with the Davies-Craig EBP, with both pumps sharings a similar design.

*) The Davies-Craig EBP price quoted is an over-the-counter cash price direct from Davies-Craig. The on-line order price is $201 AUD. (http://www.daviescraig.com.au/newproduct_ebp.asp)

*) The Eheim pumps voltages/frequency is not given as Eheim release correctly spec'ed models for whatever country they are targetted for. This means that so long as you buy the Eheim pump that is correct for your country, you should see the performance stated. The Eheim PQ curves on the literature did not have uniformally placed graph lines. The PQ curves given are based on an interpretation of the graphs using the global min-max scale of the graphs presented, and then following the points on the curve. I believe that this actually eliminates some of the discrepencies with the visual interpretation of the Eheim PQ curves that people have occasionally reported on.

*) The block flow/pressure resistance curves presented are for the blocks themselves only. They do not include additional resistances that may be introduced by a radiator or other heat-transfer device.

01-17-2004, 09:54 PM	#32
Cathar Thermophile Join Date: Sep 2002 Location: Melbourne, Australia Posts: 2,538	Posted this at OCAU. Some notes: ) This post was designed for an Australian audience. Ignore the prices listed unless you want a good laugh about how much us Aussies get ripped off on pump pricing. ) The Danner Mag 3 line is my personal interpretation of a best fit line given the data presented at their website. Their data produces a line that is not even remotely smooth, so I look the liberty to smooth it out somewhat. If anything, I may have overestimated slightly. The in-line heat figure is another approximation drawn from reading about people's experiences. I believe it to be somewhat close. ) The Swiftech MCP600 in-line heat is another approximation, based on motive pumping power which must be ultimately converted as frictional heat into the water, and some heat from the motor itself. ) The Johnson pump may be obtained for the price stated from www.depcopump.com. The in-line heat value is an approximation based on my experiences with the Davies-Craig EBP, with both pumps sharings a similar design. ) The Davies-Craig EBP price quoted is an over-the-counter cash price direct from Davies-Craig. The on-line order price is $201 AUD. (http://www.daviescraig.com.au/newproduct_ebp.asp) ) The Eheim pumps voltages/frequency is not given as Eheim release correctly spec'ed models for whatever country they are targetted for. This means that so long as you buy the Eheim pump that is correct for your country, you should see the performance stated. The Eheim PQ curves on the literature did not have uniformally placed graph lines. The PQ curves given are based on an interpretation of the graphs using the global min-max scale of the graphs presented, and then following the points on the curve. I believe that this actually eliminates some of the discrepencies with the visual interpretation of the Eheim PQ curves that people have occasionally reported on. *) The block flow/pressure resistance curves presented are for the blocks themselves only. They do not include additional resistances that may be introduced by a radiator or other heat-transfer device.