Hello,

I'm looking to buy a battery hydrometer but there are so many to
choose from: dials, floating discs, floating balls. Are they all as
good as each other or is one better to read? I'm thinking the dial
might be easiest to read.

I see that the Sealey hydrometer also has a thermometer so that you
can make temperature compensations. None of the other types has a
thermometer. Do they not require temperature adjustments? I would have
thought they would. In this case perhaps that makes the Sealey the one
to buy?

Thanks,
Stephen.

In article , Stephen
says...
Hello,

I'm looking to buy a battery hydrometer but there are so many to
choose from: dials, floating discs, floating balls. Are they all as
good as each other or is one better to read? I'm thinking the dial
might be easiest to read.

I see that the Sealey hydrometer also has a thermometer so that you
can make temperature compensations. None of the other types has a
thermometer. Do they not require temperature adjustments? I would have
thought they would. In this case perhaps that makes the Sealey the one
to buy?

It all depends on how often you're going to use it. If it's for use in
a garage, go for the Sealey. If it's going to be just now and again for
personal use, just get one of the floating disc/ball jobbies.


--
Conor

I only please one person per day. Today is not your day. Tomorrow isn't
looking good either. - Scott Adams

"Stephen" wrote in message
...
Hello,

I'm looking to buy a battery hydrometer but there are so many to
choose from: dials, floating discs, floating balls. Are they all as
good as each other or is one better to read? I'm thinking the dial
might be easiest to read.

I see that the Sealey hydrometer also has a thermometer so that you
can make temperature compensations. None of the other types has a
thermometer. Do they not require temperature adjustments? I would have
thought they would. In this case perhaps that makes the Sealey the one
to buy?

Thanks,
Stephen.

since most batteries are now maintenance free it is not likely to get used a
lot, unless you have a specialist application.

The calibrated ones (that actually read specific gravity are the best, but a
two quid floating ball type is almost as good. I used to use one for
testing motorcycle battery cells and it always seemed to give a correct
result. I really cannot remember the last time I used one at all though.

A accurate DVM is actually more use in general terms, and a loading type
tester is even better.

On Mon, 02 Feb 2009 12:18:35 GMT, "Mrcheerful"
wrote:

A accurate DVM is actually more use in general terms, and a loading type
tester is even better.

Please don't get me started on that again

I posted about battery testers a couple of weeks ago and I was told
that testing under load with a DVM was the way to go. Apparently the
people round here didn't like the load testers because the load of the
tester doesn't necessarily equal the load of your starter motor. I had
read quite a few old posts recommending load testers and was about to
buy one until everyone here talked me out of it!

"Stephen" wrote in message
...
On Mon, 02 Feb 2009 12:18:35 GMT, "Mrcheerful"
wrote:

A accurate DVM is actually more use in general terms, and a loading type
tester is even better.

Please don't get me started on that again

I posted about battery testers a couple of weeks ago and I was told
that testing under load with a DVM was the way to go. Apparently the
people round here didn't like the load testers because the load of the
tester doesn't necessarily equal the load of your starter motor. I had
read quite a few old posts recommending load testers and was about to
buy one until everyone here talked me out of it!

real world testing is good: starter load and see what the volts drop to,
but....

I use a load tester on every service to check the battery condition, but it
doubles as a very useful diagnostic for bad battery connections, engine
earths etc. Mine was from snap on and cost about 150 quid 20 years ago or
so.

"Stephen" wrote in message
...
On Mon, 02 Feb 2009 12:18:35 GMT, "Mrcheerful"
wrote:

A accurate DVM is actually more use in general terms, and a loading type
tester is even better.

Please don't get me started on that again

I posted about battery testers a couple of weeks ago and I was told
that testing under load with a DVM was the way to go. Apparently the
people round here didn't like the load testers because the load of the
tester doesn't necessarily equal the load of your starter motor. I had
read quite a few old posts recommending load testers and was about to
buy one until everyone here talked me out of it!

I don't think a load tester 'has' to equal the load of a particular starter
motor, to give give a good idea of a batterys cranking capability.
They do put a heavy load on a battery, and as long as the volts don't drop
during the test, the chances are that even a higher load wont make a
significant difference.
Mike.

On Mon, 02 Feb 2009 17:31:44 -0000, Miike G
wrote:


"Stephen" wrote in message
...
On Mon, 02 Feb 2009 12:18:35 GMT, "Mrcheerful"
wrote:

A accurate DVM is actually more use in general terms, and a loading
type
tester is even better.

Please don't get me started on that again

I posted about battery testers a couple of weeks ago and I was told
that testing under load with a DVM was the way to go. Apparently the
people round here didn't like the load testers because the load of the
tester doesn't necessarily equal the load of your starter motor. I had
read quite a few old posts recommending load testers and was about to
buy one until everyone here talked me out of it!

I don't think a load tester 'has' to equal the load of a particular
starter
motor, to give give a good idea of a batterys cranking capability.
They do put a heavy load on a battery, and as long as the volts don't
drop
during the test, the chances are that even a higher load wont make a
significant difference.
Mike.



Yep, it does, battery resistance is very non linear. If the volts don;t
drop during the test then your tester's knackered :-)

"Duncan Wood" wrote in message
newsp.uoqje3n3haghkf@lucy...
On Mon, 02 Feb 2009 17:31:44 -0000, Miike G
wrote:


"Stephen" wrote in message
...
On Mon, 02 Feb 2009 12:18:35 GMT, "Mrcheerful"
wrote:

A accurate DVM is actually more use in general terms, and a loading
type
tester is even better.

Please don't get me started on that again

I posted about battery testers a couple of weeks ago and I was told
that testing under load with a DVM was the way to go. Apparently the
people round here didn't like the load testers because the load of the
tester doesn't necessarily equal the load of your starter motor. I had
read quite a few old posts recommending load testers and was about to
buy one until everyone here talked me out of it!

I don't think a load tester 'has' to equal the load of a particular
starter
motor, to give give a good idea of a batterys cranking capability.
They do put a heavy load on a battery, and as long as the volts don't
drop
during the test, the chances are that even a higher load wont make a
significant difference.
Mike.

Yep, it does, battery resistance is very non linear. If the volts don;t
drop during the test then your tester's knackered :-)

Of course there is an initial drop when the tester is switched on after it
reads the no-load volts, but the voltage shouldn't drop during the 10 secs
or so when the test load is actually applied.

If it does drop with a fully charged battery, IME the battery is no longer
reliable.
It might still start the car in the summer, but come winter and cold
mornings and the chances are that it will not.

I've had my load tester for well over 10 years. I know how to read it and I
also know it's not knackered.
Mike..

"Miike G" wrote in message
...

"Duncan Wood" wrote in message
newsp.uoqje3n3haghkf@lucy...
On Mon, 02 Feb 2009 17:31:44 -0000, Miike G
wrote:


"Stephen" wrote in message
...
On Mon, 02 Feb 2009 12:18:35 GMT, "Mrcheerful"
wrote:

A accurate DVM is actually more use in general terms, and a loading
type
tester is even better.

Please don't get me started on that again

I posted about battery testers a couple of weeks ago and I was told
that testing under load with a DVM was the way to go. Apparently the
people round here didn't like the load testers because the load of the
tester doesn't necessarily equal the load of your starter motor. I had
read quite a few old posts recommending load testers and was about to
buy one until everyone here talked me out of it!

I don't think a load tester 'has' to equal the load of a particular
starter
motor, to give give a good idea of a batterys cranking capability.
They do put a heavy load on a battery, and as long as the volts don't
drop
during the test, the chances are that even a higher load wont make a
significant difference.
Mike.

Yep, it does, battery resistance is very non linear. If the volts don;t
drop during the test then your tester's knackered :-)

Of course there is an initial drop when the tester is switched on after it
reads the no-load volts, but the voltage shouldn't drop during the 10 secs
or so when the test load is actually applied.

If it does drop with a fully charged battery, IME the battery is no longer
reliable.
It might still start the car in the summer, but come winter and cold
mornings and the chances are that it will not.

I've had my load tester for well over 10 years. I know how to read it and
I also know it's not knackered.
Mike..

If the battery volts do not decrease to some extent when the starter
operates or the load is applied then you have the tester connected to the
wrong battery. It is a fundamental principle that the battery volts will go
down when load is applied, the extent of the drop can give some indication
of the battery condition/state of charge, with knowledge of the ambient
temperature and the size of the load you can judge battery condition.

"Mrcheerful" wrote in message
om...

"Miike G" wrote in message
...

"Duncan Wood" wrote in message
newsp.uoqje3n3haghkf@lucy...
On Mon, 02 Feb 2009 17:31:44 -0000, Miike G
wrote:


"Stephen" wrote in message
...
On Mon, 02 Feb 2009 12:18:35 GMT, "Mrcheerful"
wrote:

A accurate DVM is actually more use in general terms, and a loading
type
tester is even better.

Please don't get me started on that again

I posted about battery testers a couple of weeks ago and I was told
that testing under load with a DVM was the way to go. Apparently the
people round here didn't like the load testers because the load of the
tester doesn't necessarily equal the load of your starter motor. I had
read quite a few old posts recommending load testers and was about to
buy one until everyone here talked me out of it!

I don't think a load tester 'has' to equal the load of a particular
starter
motor, to give give a good idea of a batterys cranking capability.
They do put a heavy load on a battery, and as long as the volts don't
drop
during the test, the chances are that even a higher load wont make a
significant difference.
Mike.

Yep, it does, battery resistance is very non linear. If the volts don;t
drop during the test then your tester's knackered :-)

Of course there is an initial drop when the tester is switched on after
it reads the no-load volts, but the voltage shouldn't drop during the 10
secs or so when the test load is actually applied.

If it does drop with a fully charged battery, IME the battery is no
longer reliable.
It might still start the car in the summer, but come winter and cold
mornings and the chances are that it will not.

I've had my load tester for well over 10 years. I know how to read it and
I also know it's not knackered.
Mike..

If the battery volts do not decrease to some extent when the starter
operates or the load is applied

I think you are misreading my post.
My load tester has a spring loaded switch to apply the load.
When first connected it simply reads the no-load battery voltage. When the
switch is depressed to apply the load, the voltage reading drops.
If the voltage continues to drop, assuming the battery is fully charged, the
battery is on it's way out, and should be replaced. A constant voltage
reading during the time, (10 secs or so) the load is applied would indicate
the battery is OK.
Mike.