Product Overview

2 P20, P21 Product Bulletin
General Description
Series P20 controls feature many
desirable advantages not found in
any other controls. Exclusive,
service proved pressure element
(about the size of a quarter)
provides accurate repeat
performance -- with substantial
safety factor for long life under
extreme operating and equalized
standby pressures. Controls are
compact and ideal for panel
mounting and all applications
where space is at a premium.
(See Dimensions, Figs. 13
and 14.)
Fig. 4 -- Type P20DA with quick
disconnect terminals. Note the
contrast in size between
control and a six-inch ruler.
The contact unit is the enclosed
Pennswitch provided in SPST or
SPDT actions (see “Optional
Constructions”).
Both high and low pressure
controls are factory adjusted to
equipment manufacturers’
specifications for use on non-
corrosive refrigerants and are not
adjustable in the field. This
provides a high pressure limit stop
that meets UL requirements at no
extra cost.
Optional Constructions
Capillary
Standard 36 in. (914 mm) with
.250 in. (6.35 mm) O.D., .190 in.
(4.83 mm) I.D., sweat section
(Style 34). Available with reduced
diameter and shoulder at extra
cost, see Fig. 5. Also available
with nut and flare (Style 13).
Other lengths of capillary,
maximum 60 in. (1524 mm), or
variations supplied at extra cost.
Minimum length is 36 in.
(914 mm) when setting is over
100 lbs.
Terminals
8-32 × 1/4 in. binder head screw
terminals or single quick
disconnect terminals, as
specified, at same price. Double
quick disconnect terminals may
be supplied at no extra cost.
Terminal Cover
Molded black phenolic -- general
purpose. Spring clip snap-on
attachment. Insulating terminal
cover (Part No. 210-604) available
at extra cost when specified.
Manual Reset (trip-free)
Provided at extra cost when
specified (see “Type Number
Selection”).
Mounting
Direct by two 6-32 tapped holes
on 11/16 in. centers, see Figs. 13
and 14. Mounting bracket
available at extra cost for single
mounting (Part No. 210-25);
choice of eight positions on single
controls (Fig. 6). Bracket 211-1
for duals offers choice of four
mounting positions (Fig. 7).
Bracket 211-5 (upper left, Fig. 14)
available at same price as 211-1.
Electrical Jumper
Supplied for dual controls when
specified at extra cost.
Contact Action
SPST standard; SPDT also
available at extra cost.