Weidmuller G108 User Manual

Weidmuller Ltd.
10 Spy Court
Markham, ON L3R 5H6
Tel: [phone]
Fax: [phone]

Weidmuller Inc.
821 Southlake Blvd.
Richmond, VA 23236 U.S.A.
Tel: [phone]
Fax: [phone]

ISO 9001 Registered

Electronic Interface Modules

G108 Ultra SlimPak®

DC Input, Field Configurable Limit Alarm

n field configurable via DIP switches for

different input-output combinations

n provides relay contact closure(s) at a preset

DC input level

n field configurable input ranges 10mV to 200V,

1mA to 100mA

n setpoints programmable HI or LO and failsafe

or non failsafe

n LED trip and input indicators
n 24Vdc transducer excitation
n 9 to 30Vdc powered
n CSA approved, UL recognized, CE marked

Description

Diagnostic LEDs

Output

Operation

Dynamic Deadband

The Ultra SlimPak G108 is a DIN rail mount, DC voltage or current input, limit alarm with dual
setpoints and two contact closure outputs. The field configurable input and alarm functions offer
flexible setpoint capability. Input voltage spans from 10mV to 200V and input current spans from 1mA
to 100mA can be field configured. Bipolar inputs are also accepted.
The G108 is configurable as a single or dual setpoint alarm, HI or LO trips and failsafe or non-failsafe
operation. Also included are adjustable deadbands (0.25 to 5% of full scale input) for each setpoint, a
24Vdc voltage source (isolated from line power) for transducer excitation, and a flexible DC power supply
which accepts any voltage between 9 and 30Vdc.

The G108 is equipped with three front panel LEDs. The green LED is a dual function LED labelled INPUT.
This LED indicates line power and input signal status. Active DC power is indicated by an
illuminated LED. If this LED is off, check DC power and wiring connection. If the input signal is
above 110% full scale, the LED will flash at approximately 8Hz. Below 0%, the flash rate is 4Hz.
Two red LEDs indicate the relay state for each setpoint. An illuminated red LED indicates the tripped
condition.

The G108 is equipped with two SPDT (form C) relays, rated at 120Vac or 28Vdc at 5 amperes.
Each of these relays is independently controlled by the field configurable setpoint and deadband.

The field configurable G108 limit alarm setpoints can be configured for HI or LO, failsafe or non-failsafe
operation. Each of the setpoints has respective HI or LO deadband. In a tripped condition, the
setpoint is exceeded and the appropriate red LED will illuminate. The trip will reset only when the
process falls below the HI deadband or rises above the low deadband (see Figure 1). For proper
deadband operation, the HI setpoint must always be set above the LO setpoint. In failsafe operation,
the relay is energized when the process is below the HI setpoint or above the LO setpoint (opposite
for non-failsafe). In the failsafe mode, a power failure results in an alarm state output.

LSI circuitry in the G108 prevents false trips by repeatedly sampling the input. The input must
remain beyond the setpoint for 100 milliseconds, uninterrupted, to qualify as a valid trip condition.
Likewise, the input must fall outside the deadband and remain there for 100 milliseconds to return the
alarm to an untripped condition. This effectively results in a “dynamic deadband” based on time in
addition to the normal deadband.

+

Figure 1

Table 1: G108 Input range switch settings (SW1, 1 through 4) KEY z = ON

(optional)

47 ohm

1/2W

47 ohm

1/2W

Load

Load

Diode

MOV

0.1uF

0.1uF
Film

Film

Relay

Conta cts

Figure 2: DC Inductive Loads

Relay

Conta cts

Figure 3: AC Inductive Loads

Power

Power

-