Poseidon P190

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

The Monkey

Registered
Messages
6
Reaction score
1
Location
The Jungle
Tried this query on another forum, but not much of a response so far. Hoping for better luck here:

I’ve had a Poseidon P190 compressor for many years (powered by a Briggs & Stratton Vanguard petrol engine) giving good service. Probably not maintained nearly as well as it should have been but that’s another story. Anyway, recently I decided to remove the engine and replaced it with an electric motor (so that I can run it indoors). As the motor was smaller (3HP) than required to drive the compressor at full tilt (manual says compressor demand is 4.7HP), I had to use a smaller pulley on the motor than the engine had and now the rpm is 800 (calculated then checked with tacho once running) against the manual’s stated max of 1300. Obviously flowrate is down but I can live with that as I’m only topping up 3L CCR and 1.5L suit inflate bottles these days. All seems to be running fine and I’ve filled a few small cylinders already. However, I’m a bit nervous about the internal lubrication at the lower rpm. The manual states that it’s a splash lube with oil extractor pin on con rod of 3rd stage. HP stage lubricated by oil vapour. Can anyone tell me how much of an issue the lower rpm will be for the splash lube?

A couple of other related queries while I’m on:

1. I changed the rotation (via motor wiring) as the flywheel on the compressor was spinning the wrong way when using the (non-reversible) petrol engine, and the fins were pushing the coolant air away from the compressor rather than across it. Again manual seems to indicate 2 different flywheels available, depending on prime mover rotation direction, and I’m assuming when the engine was put on either the direction of rotation and the angle of the fins on the flywheel wasn’t noted or they couldn’t be bothered to change the flywheel. Is it OK to reverse the direction (again I'm thinking mainly about lube here and if the splash is via some 'paddle' that relies on the correct direction to work properly)?

2. Manual states Shell Ensis oil but I’d like to change out to Anderol 555. Would this cause any issues? Change out/flush procedure would be basically; run till warm, drain, fill with 555, run 15mins, drain, then fill with 555. Would Shell Corena P68 be another option?
 
I think that's too slow to properly lube the pump. I'd try to get it back up to 1000rpm. Does the manual call out a 4.7hp gas motor, or electric motor? Two very different situations with those. 5hp down to 3hp is a lot, but scaling back by 20% or so is pretty normal.

1. most electric motors can be reversed with no issue. I would leave the pump turning at whatever direction it was with the combustion engine and sort out direction with the electric motor. I've never heard of a pump being able to turn backwards for the same reason that a combustion engine can't run backwards *they work the same way*.

2. I'm not particularly well versed in converting to synthetic oil, so I can't comment on that.
 
Thanks for the reply tbone1004.

Manual calls out 4.7hp for power demand to run pump at 1300rpm which is stated as a maximum rpm. No minimum rpm is given. The options given in the manual (I’m guessing originally available when buying) are electric motor at 5.35hp and engine at 6.5hp. The engine previously fitted was 9hp so probably not supplied with the compressor originally, and maybe another clue that it may have been originally powered by an electric motor, spinning the opposite way from the engine. If push comes to shove I could get a 4hp motor and increase pulley wheel from 120mm to 150mm to get 1047rpm (calculated), and if I can get the same frame size it should fit on the bracket I welded up for mounting, but I’m not sure my supply could take the starting current?

I’ve reversed the motor already and no problems there. The wiring diagram on the inside of the cover gave both CW and CCW options. The compressor now spins in the opposite direction from when the engine was fitted and now the fan/flywheel is blowing cooling air across the pump as it should. As I said the manual appears to give two options of flywheel labelled CW and CCW so this would suggest it’s OK to spin the pump in either direction? It seems to be running fine and I’ve already filled cylinders to 230bar. Although the pump and an engine ‘work the same way’ in principle i.e. pistons being driven up and down by a spinning shaft via con rods etc, I think there’s enough of a difference that the pump doesn’t care which way the shaft turns (I believe some simple engines can run backwards too?). If it were ‘running backwards’ wouldn’t it be trying to suck from the outlet and blow from the inlet?

I’m trying to find a contact in Bauer (who own the Poseidon brand) who can advise about the speed, direction and oil type. I’ll come back and share if I get any answers.
 
Hi,

All Poseidon compressors were made in Wiener Neustadt, Austria. You can contact them via email, (info@bauer-kompressoren.at). They have always been super responsive. I raised the same question about the minimum RPM, but for the 320Bauer (k12.14) block which has an oil pump for lubrication and I was told that the minimum RPM is determined by the cooling air flow rather than oil pressure. For the 12.14Bauer Mariner block it is 900RPM to provide sufficient cooling, which would still maintain the oil pressure between 3-6 bars. Just email them and they will help you out. I hope it helps.

Roland
 
@The Monkey if it says it needs a 5hp electric motor, I'd be very hesitant to run it on a 3hp. Too slow for the lubrication to work properly IMO. If it calls for 5.35hp @1300rpm, with a 3hp motor, you won't be able to go over 700-800rpm which is where you are which is almost half speed. You should be able to get 3/4/5hp motors in the same frame size and bolt right in. You will potentially need to get a soft start or VFD for the motor and I would recommend putting one on. They aren't that expensive, but can be quite important.
Assuming you're in the US with 1p 240vac, you'll want a 30a circuit to comfortably run that motor. 30a on 1p/240vac is standard dryer plug circuits btw and a 5hp motor is "standard" for home sized compressors.

The issue with direction is going to largely come from the oiling mechanism and any cams that it uses *if it uses any*. The crank shafts don't really care, but the valves need to open in the right order, and I'm not familiar with that pump to know how it's designed.
On the fan though, you can always replace it with an electric fan and give it maximum cooling which is what I'm doing with my Rix SA6
 
Thought I'd come back to this (quite old) thread to close it out with what I learned (for posterity).

I managed to speak to a nice chap from Bauer in Austria who offered the following:

• Lowest rpm recommended is around 10-15% below the 1300 stated in the manual (I've put on a bigger pulley and now somewhere around 1100rpm for the past 9 months or so with no issues. I thought the motor would crap out but ok so far).

• Reversing the direction of rotation is fine (to get the flywheel blowing air over rather than away from the compressor).

• Don’t use synthetic oil, only mineral. He recommended Shell Corena P150.
 

Back
Top Bottom