Fisher 304 - Page 2

Type 304 & 304L
2
Table 1. Specifications
Available Configurations
Type 304: Unit contains 1 or 2 switches
Type 304L: Unit contains 3, 4, 5, or 6 switches
Maximum Cam Rotation
90 degrees between point of actuation of first switch
and point of actuation of last switch
Switch Type
Single-pole, double-throw
Switch Electrical Ratings
Service Ratings (when wired at the factory): See
tables 2 and 3
Maximum Continuous Current: 20 amperes
Maximum Inrush Current: 30 amperes with normal-
ly-closed contacts; 25 amperes with normally-open
contacts
Electric Motor Rating: Capable of switching a 3/4
horsepower electric motor at 125 V ac or a 1-1/2
horsepower motor at 250 V ac
Hazardous Area Classification
Refer to the Hazardous Area Classification bulletins
and the switch nameplate (see figure 2 for typical
nameplate)
Operating Temperature Range
(1)
–40_ to +180_F (–40_ to +82_ C)
Conduit Connection
With Bushing: 3/4-inch NPT female connection ac-
cepts a maximum of six 14-gauge wires
Without Bushing: 1-1/4 inch NPT female connection
accepts a maximum of eighteen 14-gauge wires
For Explosion Proof Installation: Appropriate con-
duit seal is required 18 inches (460 mm) from hous-
ing
Approximate Weight
Type 304 (with 2 switches and cover): 5 pounds
(2.3 kg)
Type 304L (with 6 switches and long cover): 10
pounds (4.5 kg)
Options
Terminal Strip
1. This term is defined in ISA Standard S51.1-1979
Table 2. Direct-Current Service Ratings
NON-INDUCTIVE INDUCTIVE
DIRECT
CURRENT
Heater Load Lamp Load (Tungsten) Motor, Relay, or Solenoid Load
DIRECT
CURRENT
Normally Open
Contact
Normally Closed
Contact
Normally Open
Contact
Normally Closed
Contact
Normally Open
Contact
Normally Closed
Contact
V olts (DC) Amperes Amperes Amperes Amperes Amperes Amperes
6-8
12-14
24-30
110-115
220-230
15
15
6
0.4
0.2
20
20
6
0.4
0.2
1.5
1.5
1.5
0.4
0.2
3
3
3
0.4
0.2
15
10
5
0.05
0.03
20
10
5
0.05
0.03
T able 3. Alternating-Current Service Ratings
NON-INDUCTIVE INDUCTIVE
ALTERNATING
CURRENT
Heater Load Lamp Load (Tungsten) Motor, Relay, or Solenoid Load
ALTERNATING
CURRENT
Normally Open
Contact
Normally Closed
Contact
Normally Open
Contact
Normally Closed
Contact
Normally Open
Contact
Normally Closed
Contact
V olts (AC) Amperes Amperes Amperes Amperes Amperes Amperes
110-115
220-250
440-480
20
20
20
20
20
20
2.5
1.25
0.75
3
2.5
1
15
15
2.5
15
15
2.5