Gems Sensors Inc.
One Cowles Road
Plainville, CT 06062-1198
Tel: 860-793-4579
Fax: 860-793-4580
Wiring Diagrams
Notes:
1. Factory-installed resistor (See resistor table)
2. Factory-installed jumper
3. The reference connection must be a metallic vessel or probe
4. Dashed lines represent field connections
5. Open version only is UL recognized (UL 353 File: MP1430)
Warrick®Series 2820 Seal Leakage Detector
Installation and Operation Bulletin
P/N 7800978
Rev C
This bulletin should be used by experienced personnel as a guide to the installation of Series 2820 controls. Selection or
installation of equipment should always be accompanied by competent technical assistance. We encourage you to
contact Gems Sensors Inc. or its representative if further information is required.
Specifications
Contact Design: 2PST and 3PST bridge type double break in
all possible combinations of normally open and normally
closed. Fully enclosed. Buttons are 1/4 inch diameter silver
cadmium oxide.
Contact Rating: 16A @ 115 VAC, 8A @ 230VAC, 1 H.P. @
115, 230 VAC
Mode of Operation: Direct only. Contacts assume normal
position with open circuit.
Supply Voltage: 115, 230, 406 or 575 VAC models: +10% -
15%, 50/60 Hz
Supply Current: Relay energized 4.4 VA
Secondary Circuit: 500 VAC on probes, 6 VA with short
circuited electrode circuit
Sensitivity: 20K Ohms/cm (150’ maximum distance between
control and probes).
Temperature: -40° to 150°, ambient
Terminals: Size 8 pan head screws with wire clamping plate
for use with captivated wires or a maximum of 1-#12 AWG/2-
#14 AWG uncaptivated wires. Numbered 1 to 10 for identifica-
tion. Located on front of control assembly for accessibility.
Listings: UL limit control recognized (353) on open type
controls only.
General
The Type 2820 is a conductance-actuated control for detection
of moisture in the oil chamber of a submersible motor. It is
used as a warning device to indicate a seal leakage and to
signal the need for preventative maintenance.
Installation
Mount the control or enclosure vertically on wall or other solid
structure, with the transformer on the left-hand side. Wire
Series 2820 as indicated on drawing. Terminals on the control
are numbered and are in the same relative position as shown
on the wiring diagram. Terminal pair 1 and 2 must be continu-
ously energized from an AC supply line of electrical character-
istics shown on the data plate. Contacts 5-6 and 7-8 are
available for load duty and, if required, must be wired in series
with the load device(s) and load. Terminals 9 and 10 connect
to the moisture sensing probe in the motor marked W1 and
Ground Reference via cable provided with the motor.
Caution: Probe Sensing circuit, terminals 9 and 10, have 500
VAC, 12mA. This high voltage has minimal amperage, but can
cause significant shocking.
Operation
Normally the oil surrounding the probes is nonconductive and
the control will be de-energized. An influx of moisture past the
outer seal and into the oil reservoir will change the conductivity
of the oil and cause the relay to energize. Note that the
moisture may not cause this change in conductivity until
motor is running and the moisture becomes emulsified
Operation (Cont.)
with the oil. Load contacts 5-6 and 7-8 will change from their
normally open or normally closed position when the control
energizes.
Test Procedure
To simulate a seal leakage, the following test should be done.
Caution: Voltage will be present at all terminals on the
control when this test is being made:
Remove the enclosure cover and momentarily place an insu-
lated jumper (or 20K ohm resistor) across terminals 9 and 10
on the control. The control should energize, simulating a leak
condition.
Wire control per drawing, following NEC and local codes. Use
appropriately sized spade terminals when wiring.
Ordering Information
Model 2820 X X X Moisture Detectors
Basic Model of Moisture Relays
Supply Voltage
1) 115 VAC
2) 230 VAC
4) 460 VAC
5) 575 VAC
Contact Configuration
D) 1 N.O. & 1 N.C.
E) 0 N.O. & 2 N.C.
G) 2 N.O. & 1 N.C.
H) 1 N.O. & 2 N.C.
J) 0 N.O. & 3 N.C.
Enclosure Type
0) Open - No Enclosure
1) NEMA 1
4) NEMA 4
