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Dimensions
The FM/1 digi 20 is a compact electronic 24 hour/
7 day time switch module, with heavy duty relay contacts
for switching low or line voltage loads. Applicable for
time of day control of pumps, fans, heaters, HVAC con-
trol circuits, lighting, machinery and many other types of
commercial, industrial, and agricultural equipment.
The FM/1 digi 20 model features large keys with
unique “circular programming” for easy programming, a
large LCD display and capacitor backup to retain pro-
gram memory during power outages.
TECHNICAL DATA:
Channels: 1
Programs: 20
Holiday Program: No
Daylight time changeover: Manual
Manual 3 way override: On-Auto-Off
Shortest switching time: 1 minute
Reserve carryover: 100 hrs.
Input voltage models available:
24VAC/DC; 120VAC; 208/240VAC
Switching output: SPDT relay
Switch ratings:
16A res. @ 277VAC
1000W Tungsten @ 250VAC; 500W @ 125VAC
SPECIFICATIONS:
Input draw: 4VA
Input frequency: 50 or 60Hz
Wiring connections: 1/4” quick connects
Ambient temperature: –20°F to 140°F (–28°C to 60°C)
UL and Canadian UL recognized: File E83486
INSTALLATION & WIRING:
Note: Although the FM models contain some degree of spike and elec-
trical noise protection, as with all electronic devices, these units can be
affected by electrical noise. Therefore, it is recommended that they be
powered from a voltage source that has no switching devices or inductive
loads connected.
1. Check the input and output ratings marked on the unit to make sure
this product is suitable for your supply voltage, load, and application.
2. Disconnect supply power prior to installation to prevent electrical
shock.
3. Install in accordance with all applicable National and Local electrical
code requirements.
MOUNTING OPTIONS:
The standard FM/1 models may be surface mounted inside a panel or
flush mounted with MK-FM mounting kit, available from Grasslin. Indoor
NEMA 1, and outdoor NEMA 3R enclosures are available for stand-alone
mounting. Consult Grasslin catalog or price sheet for various options.
A mounting base (MB-FMPC) is available for printed circuit board
mounting. A clear plastic dust cover (DC-FM) is also available.
Models are also available with screw terminals and DIN rail mounting,
or for flush mounting with housing and clear cover. (Digi 20A & Digi 20E)
FM/1 digi 20
One Channel Electronic Time Switch
Terminal Connections
M
LOAD
POWER
TIMER INTERNAL WIRING
COM
NO
NC
TIME
SWITCH
FIELD WIRING
1
2
3
4
5