On 6/4/2016 4:32 PM, Mark Lloyd wrote:
On 06/04/2016 02:30 PM, Frank wrote:

I hear about the Simply Safe home alarm system which you install
yourself and is cheap with no wiring. You can bet cost of battery
replacement is a big negative.

The "cost of battery replacement" is something I think of every time I consider
use of a battery-operated device in a fixed location. Some can be modified to
use an external power source. I do have one wired like that now, a remote
switch for "Lilly's lights".

I don't think of the "cost" in terms of the cost of replacement batteries
(which can be small, esp if using rechargeables).

But, rather, the cost in terms of inconvenience and (un)reliability
for a battery operated product. E.g., I won't purchase power handtools that
are battery operated. I want to KNOW that I can use a tool the moment I
take it off the shelf; the "inconvenience" of a cord is a non-issue.
Esp when contrasted with the inconvenience of having to wait for a battery
to charge *or* recharge while using the device (and, when the battery
ultimately fails is some time when you are USING the device).

The convenience of battery (portable) power can be obtained without
the RELIANCE on battery power!