Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Topics - millman56

Pages: [1]
1
Generators / Over excited
« on: February 28, 2014, 09:43:01 PM »
Hi,  I`m seeking advice about a recently aquired Allam 10 KVA 415 Volt generator, this is assumed as there is no spec plate and it has a 20HP engine.  It came with a trashed doghouse containing various bits and pieces of what appeared to be the original transformer regulator/rectifier setup,
The alternator has 6 wires emerging from the main stator which I have connected star,  also there are 4 wires  (3 + N )  of what seems to be a three phase auxillary winding, the exciter field is fed by slip rings and brushes, one brush is grounded.   
                                                                                                                                                                                                                                        To liven it up a battery charger was connected  to ground and the + wire of the field, this gave 105 or so volts phase to neutral,  the next move was to fit an AVR feeding from phase to neutral,  the output was dead until the battery charger + was touched on a phase terminal, this livened it up with an output voltage phase to neutral of 235 volts,  all well and good,  it seemed happy boiling a kettle,  albeit with an 8 volt drop,  however when attempting to start a 3hp 3 phase motor, the output faded away completely.   

With the AVR connected the no load voltage measured at the  auxillary output was 82 volts phase to phase, the AVR was then configured 110 volt input and connected to 2 of the auxillary phases, the false Eureka moment came when the thing powered up without DC  assistance,   my hopes were dashed when it was impossible to raise the output volts to more than 215 using the AVRs voltage trimmer and it wouldn`t start the motor.


Next brainwave was to fit a 3 phase rectifier to the auxillary AC output and feed its DC output into the field,  this self exited but a bit too much, 266 volts in fact, dropping the frequency down to 46 HZ gave a perfect 237 volts phase to neutral and it would start the motor no sweat with an 8 volt drop.
So my question is how best to reduce the  current to the field to enable 50 HZ operation at a sensible no load voltage?                                                                                             
I did try putting a big variable resistor in series with the DC output but it didnt make any difference.   

Mark.                                         










2
Generators / Markon Alternator Connections
« on: May 13, 2013, 11:26:44 AM »
Can anyone put me right on this please.     A recently aquired  4 pole single phase  Markon 10 Kva generator is marked 110/55 volts on the spec plate,   there are 4 pairs of wires on the connection block connected in series.   My question is as there are 8 ends in total would this alternator be reconfigurable to 220 volts ?  

Thanks in anticipation,

Mark.

3
Engines / Petter AD1 piston clearance
« on: March 28, 2013, 11:41:07 PM »
Anyone know the nominal piston clearance for a Petter AD1 ?   

Mark.

4
General Discussion / Speed increasing belt drive
« on: September 10, 2012, 11:18:35 PM »
Recently I visited a 100 year old water turbine which was repaired and reinstated about a year ago, it is a Gilbert Gilkes and Gordon (still in business) Francis Wheel and is driving an 8 pole 18.5 Kw grid tied induction motor via a speed increasing vee belt drive, 4 groove "B" section 32" to 6".   The setup has over 8,000 hours on the original belts and apart from 1 belt sitting a little lower in its groove than the others they`re showing little wear and a look at the slide rails shows the motor has been adjusted less than an inch in a year of 24/7 running.           It was putting  14.4 Kw into the grid and this would be a good average as on commisioning it was doing over 15.       
Although this drive is operating in ideal conditions, clean, dry,cool and smooth prime mover/ load characteristics,  it still says a lot for a conventional belt drives durability.
Does anyone have any data for the life of belts fitted to a SOM set ? It would be interesting to know how a pulsating and oily prime mover affects belt life.

Mark.

5
Original Lister Cs Engines / Fuel consumption
« on: July 14, 2012, 08:15:53 AM »
Hi, 
In my Lister FR manual is a set of graphs showing consumption curves at various outputs and speeds, the graphs cover the engines from FR 1 through to FR 6, I know they are a bit different to the CS range but do employ a very similar combustion chamber design.
The FR 1 figures ( this is as close a number as possible from the graph ) show 1000 Rpm 4.9 Hp  and 0.75 Imp galls per hour and at 1500 Rpm 7.5 Hp 0.9 Imp galls per hour.   The fuel consumption in pounds of fuel used per B.H.P. hour as a percentage of load at 1500 Rpm show 100% loading to be the most fuel efficient,   the actual numbers being 0.47 lbs Bhp hr @ 100% load with a fairly even convex curve to 0.62 lbs Bhp hr @ 45% load. 
What is interesting  is the difference in specific fuel consumption  between an FR 1 and an FR 6,  0.47 lbs Bhp hr and 0.425 lbs Bhp hr respectively at 100% loading,   this would indicate the better mechanical efficiency of multi cylinder engines.
My thoughts are that  our actual usage of engines  will always be a compromise between many factors and the manufacturers figures are no more than a starting point for most.

Mark.

6
Everything else / Engine Governor
« on: April 10, 2012, 07:32:37 AM »
Hi,    an 85 KVA generator I have in my shop presently, has an electronic speed governor fitted, this holds the RPM perfectly with varying loads, in fact I ran the machine with the governor detached and a fixed  no load RPM set on the pump control arm (CAV DPA ) and the speed  governing was hopeless at  20% load.
Now not being one to spend uneccesary cash, having a couple of generators I use for my shop power and proprietary speed governors being very expensive, I thought about the possibility of using a vehicle cruise control set up which I assume is a similar closed loop system to an electronic governor.
The problem for me, not being an electronics whizz, would be modifying the electronics of the system to suit, is there anyone who has done this or would know the mods needed ? 

Thanks in anticipation,

Mark.

7
Lister Based Generators / Startomatic regulation/governing ?
« on: January 30, 2012, 09:49:18 PM »
Hi,
can anyone help me out with a Startomatic problem please ?    When setting up a 220 volt 4.25 Kva (unity pf) Lister VA Startomatic set, initial settings, alternator 233 volts @ 1523 Rpm no load,   2200 Watt resistive load applied, 204 volts @ 1475 Rpm. This seems to be very poor regulation compared to a 240 volt 4.5 Kva  (unity pf) 8-1 set with a "Fatboy alternator"  which only dropped 4 volts with the same 2200 Watt load.    As I am not a regular Startomatic user and what I need to know is do the non fatboy alternators have poor regulation or do I have a fault. The engine governor linkage appears to be fine as switching the load in and out gives identical results every time.  The way I set it was Rpm firstly then voltage via the shunt resistor.   

Thanks in anticipation,   Mark.

8
Generators / Lima Elecrtic Co MAC R - VR3
« on: October 18, 2011, 08:57:30 PM »
Hi,

Does anyone out there know if its possible to increase the excitation current on a Lima MAC R  alternator?   Tickle its fancy I hear you say,  my problem is that I have a  4 pole 15 Kw 12 wire 60 Hz 416/240v star 120/208v delta alternator I wish to run at 1500 Rpm in order to acheive 50 Hz 415v, this speed only gives out about 350 Volts.    these alternators have no AVR so its not a case of just tweaking up the volts.
My instincts tell me that its impossible with its present rotor but it would be good to be told otherwise.

Mark.

9
Waste Motor Oil / Tractor oils
« on: April 17, 2011, 09:04:13 PM »
 Those living in rural areas with a need for a fairly light oil without too much contamination, could do worse than to ask their local farmers about their used tractor oils, some of the newer big and fancy tractors hold as much as 30 gallons of thin oil in the back end which needs changing at 1500 hour intervals, on large farms this adds up to a lot of oil.    One of the problems I have found but thankfully quite rare, is getting a 45 gallon drum home only to find its half full or more of water.    Some of the oil has hardly needed thinning before use and in my view is is a superior alternative to WMO as a diesel substitute.  Not tried it in a Lister yet but both my Perkins 4-270 D genset and IH 3434 tractair love it with only a little more smoke than when diesel fuelled.

Mark.

10
Lister Market Place (things for Sale) / Lister CS 6-1 Startomatic Engine
« on: January 06, 2011, 12:26:39 AM »
Lister CS 6-1 Startomatic type engine, s/n 231617, it has the heavy flywheels, one flywheel has two B section vee belt grooves machined in it for belt coupling to a generator head, this engine is good for a 2.5 Kw continuous load, it has a working valve lifter/fuel cut off solenoid fitted.
The engine starts easily and runs well without known faults.   It has frost damage in the usual place that has been repaired to a high standard and is missing the rocker cover, these are cheaply available.  The engine can be seen running on Youtube entitled "Richards Lister CS 6-1 Startomatic Engine" photos will be posted in my photo gallery soon.   Bids to be sent via PMs to myself or DrDeath and the final price will include delivery to Dodge City Ks.  Thank you for your interest, Mark.

11
Lister Market Place (things for Sale) / Lister 3-1 Engine
« on: November 26, 2010, 12:26:36 AM »
Lister CS 3-1, in original condition, its difficult to start in freezing weather despite good compression but once started runs without fault, no frost damage,   s/n 87987 spec 208/15 . can be seen running on Utube entitled " Marks Lister CS 3-1". Photos in millman56 gallery.  To be sold in the same way as the CHP engine.

12
Lister Market Place (things for Sale) / Original Lister 5-1 CHP Rig
« on: November 24, 2010, 10:29:46 PM »
Lister 5-1 s/n 1991513 prototype CHP system, tube and shell exhaust heat exchanger (splits for cleaning ) on the exhaust piped in parallel with the engines colling jacket,  5 Kva 50 Hz 110 volt alternator, electric start and stop, fuel lift pump, HD angle iron frame.  The engine starts and rus well without known faults and the alternator produces power.  See Youtube "Marks CHP Setup".   It has had a repair to frost damage in the usual place behind the pushrods.    Photos in gallery Millman56.   This rig and a good few more original Lister CS engines will be sold by auction on this forum. The details have yet to be finalised although the general idea is that the auction price will include delivery from the UK to KS, from there it will be up to the buyers to get them home.  Mark.

13
Original Lister Cs Engines / Access Again
« on: November 04, 2010, 12:28:50 AM »
Hi everyone, a few lines to introduce myself, I live in the UK about right in the centre and have an unhealthy interest in all things compression ignition. It is a friend and I who are planning to send a container of Lister CS and other types over to the US as  Dr Death has made known here and elsewhere.   Millman56.

Pages: [1]